Kerno ERP: the ERP for Shopify and Amazon brands
Run the whole business on one system.
From factory order to invoice, for Shopify and Amazon brands. Your whole team sees where every unit is, what it cost and what it earned, and nobody has to call around to find out.
- Built by ecommerce owners, to run our own brands
- Nothing is ordered, sent or changed until you say so
- Purchasing
- Purchase orders in the factory’s currency, receipts and landed cost.
- Stock
- Every warehouse, 3PL and Amazon FBA location, on one count.
- Orders
- Shopify and Amazon orders, reserved against real stock.
- Fulfilment
- Picking, packing and shipping, in your warehouse or at your 3PL.
- Returns
- Inspect, restock and refund, with the cost put back right.
- Kits
- Bundles and bills of materials, down to the component.
- Accounts
- Cost of goods on every sale, with QuickBooks Online and Xero.
Your tools each know part of the story. Kerno knows all of it.
Shopify knows what sold. Your ads know what you spent. The factory’s email says when stock ships, and your books know what you paid. Kerno reads them together, so it spots what none of them can see alone, and tells you what to do about it. That includes whether to spend more on ads: MER against your break-even, new-customer cost against what customers earn, and whether stock and cash can take it. Four moments from our example store:
Ads and stock
At December’s pace the bottle sells out on 3 Jan. PO-124 lands 12 Jan. Your Google Shopping ads would send buyers to a sold-out page for 9 days.
Read together fromShopifyPurchase ordersForwarder trackingGoogle Ads
Hold the bottle’s ads from 3 Jan and restart them the day PO-124 is received. That keeps about $4,200 for products you can sell.
With separate tools: Google keeps spending. You see it on the bill.
Late factory
Ningbo Steelware said PO-121 would land 27 Nov. The forwarder’s tracking says 10 Dec, 13 days late, and only 1 of its last 3 orders arrived on time.
Read together fromFactory emailsForwarder trackingPurchase orders
Plan Ningbo Steelware at 38 days, not the 25 it quotes, so the next bottle order goes today instead of in 13 days.
With separate tools: The factory’s date goes in the spreadsheet. You find out when the shelf is empty.
Wholesale quote
A stockist wants 500 bottles. They cost you $9.39 landed, with duty and freight. Shipped from stock now, they’d sell your bottle out on 22 Dec, in the December peak.
Read together fromPurchase ordersQuickBooksShopifyAmazon
Quote $15.00 a bottle for delivery from PO-124 on 12 Jan. That earns $2,425 after a $380 pallet, and the bottles in stock stay for your December shoppers.
With separate tools: Three spreadsheets, an email to the forwarder, and a guess at the margin.
Cash
March’s supplier payments come to $16,400, $4,400 over the $12,000 a month you set aside for stock.
Read together fromPurchase ordersQuickBooksShopify
Split the cold brew jar order into two shipments a month apart, so half the payment moves to April and stock never drops below safety.
With separate tools: You find out from the bank balance in March.
- It shows its reasons. Every suggestion says what it read and why, in plain words.
- It asks first. Nothing is sent, paused or ordered until you say yes, or turn on autosend for that step.
- Your data stays yours. Never used to train anything, and you can export all of it whenever you like.
- It works with what you have. Shopify, Amazon, your ads, QuickBooks Online and Xero.
From factory order to invoice, in one flow.
Every stage your stock goes through, from the factory to your accounts, on one record. Your whole team sees where every unit is, and nobody has to call around to find out.
Buy
1Purchase order to your manufacturer
Orders sized on what really sells, sent in seconds.
Kerno drafts the PO from the forecast, in the factory’s currency and on your terms. Confirm it, or autosend.
Stock now: In production
2Production
No more chasing the factory for dates.
Live production status on every PO: deposit, in production, quality check, ready. A slipped date updates every plan.
Stock now: Ready
3Shipment
Customs papers without retyping a line.
Packing list and commercial invoice in one click. Tracking, freight and duties sit on the shipment.
Stock now: In transit
4Warehouse receipt
Every warehouse, one live stock count.
Counted in against the PO, at any warehouse. Shorts and damage flagged on the spot.
Stock now: Received
5Components and builds
Know when every build can start.
Each part tracked as its supplier ships it. See what you can build today, then run the build: parts used, finished stock and its full cost booked.
Stock now: Built
Sell
6Customer order
Never sell the same unit twice.
Shopify, Amazon and wholesale in one list. Stock held for each order the moment it arrives.
Stock now: Allocated
7Warehouse release
The right warehouse, every time.
Kerno picks the warehouse with stock. Change the criteria, fastest delivery or cheapest shipping, in settings.
8Shipping
Out the door in one step.
Labels, packing lists and customs invoices. Tracking goes to the customer and the channel.
Stock now: Shipped
9Delivered
Know it arrived before the customer tells you.
Delivery confirmed by the carrier. Returns start from the same order.
Stock now: Delivered
Account
10Invoice in your accounts
Books that match the warehouse.
Invoices, cost of goods and supplier bills sync to QuickBooks Online or Xero. Nothing retyped.
One record from the factory order to the invoice. Nothing typed twice, nobody to call for a status, and every unit’s place known at a glance.
- Documents on everything
- Attach shipping docs, customs and import papers to any PO, shipment or order, and forward an email to file it there.
- Your team stays out of the accounts
- Anyone can check stock and process orders in Kerno, each with the access their job needs. Only your accountant opens the books.
Built for small teams: a simple SKU count, a few users, no ERP project. Get early access
What you see once it’s connected.
Kerno Forecast shows what to buy, when and why, from purchase orders to Amazon FBA. Kerno Insights shows what each product really earns, and your best seller by revenue might be losing money. Switch products, then click through the tabs.
Overview
Every product across Shopify, Amazon and your warehouses, as of 5 Dec. Recalculated each morning.
- Buy list$9,421What the suggested orders cost, at each supplier’s price.
- Products to order this week4Products whose order-by date is in the next 7 days.
- In-stock rate91%Share of selling days each product was in stock, weighted by its sales. Last 90 days.
- Sales lost to stockouts$24,800Sold-out days × in-stock daily sales × price. An estimate. Last 90 days.
- Stock on order$10,310Open purchase orders not yet received, at cost.
- Overstock$5,240Cost of stock with more than 180 days of cover, or unsold for 90 days.
- Forecast accuracy87.0%1 − (units forecast wrong ÷ units sold), per product, last 3 months.
- Days of cover51 days(On hand + on order) ÷ in-stock daily sales. Median across products.
- Stock turns5.2×Cost of goods sold in the last 12 months ÷ average stock at cost.
- Supplier delay10 daysAverage days the last 3 orders arrived after the supplier’s quoted date.
Needs you today
Order 840 insulated bottles today.Ningbo has taken 38 days, not 25. Ordering later than today means a sell-out around 9 Jan, in the January sale.
Order cold brew jars and black mugs by 8 Dec.One Jingdezhen order for both, so the mugs ride in the same shipment.
3 purchase orders are late.The 200 bottles and 400 mugs are already counted, at their new dates. Chase the 200 straw packs Ningbo didn’t ship.
Black mugs at Amazon drop under 28 days this week.Send 90 from New Jersey before Amazon starts its low-inventory fee.
Gift boxes are covered for the peak.650 arrive from Leeds on 9 Dec, before the last week of Christmas orders.
Buy list
What to order, how many and by when. The order-by date allows for each supplier’s real lead time plus 7 days of safety stock.
| Product | Sold a day | On hand | On order | Days of cover | Lead time | Order | Order by | Why |
|---|---|---|---|---|---|---|---|---|
| Insulated bottle, 750 mlNingbo Steelware, $6.40 each | 30 | 1,100 | 200 | 43 | 38 days | 840$5,376 | Today | Out of stock 27 of the last 90 days; the December peak is inside the cover window. |
| Spare bottle lidNingbo Steelware, $0.90 each | 9 | 420 | – | 47 | 38 days | 350$315 | 6 Dec | 5 of its 9 a day sell inside two bundles. Rounded up past the 300 minimum. |
| Steel straw packNingbo Steelware, $1.20 each | 6 | 380 | 200 | 97 | 38 days | 500$600 | 25 Jan | Not due until 25 Jan. Added to this Ningbo order so it ships in the same run. |
| Cold brew jarJingdezhen Ceramics, $5.50 each | 8 | 410 | – | 51 | 41 days | 420$2,310 | 8 Dec | Sales up 4% a month since June. The last 3 orders took 41 days, not 25. |
| Travel mug, blackJingdezhen Ceramics, $4.10 each | 19 | 580 | 400 | 52 | 41 days | 200$820 | 8 Dec | 400 already on order, so only 200 more. Goes on the same order as the jars. |
| Gift box setLeeds Print & Pack, $11.00 each | 25 | 300 | 650 | 38 | 21 days | – | Covered | 650 arrive 9 Dec and cover the rest of the peak. Sales fall to 6 a day in January. |
| Buy list | $9,421 | |||||||
Sold a day leaves out the days a product was sold out, and counts every bundle sale on each product inside it. Quantities round up to the supplier’s minimum and the bottle’s case of 24. Change any quantity and the purchase order follows.
Forecast
One model per product, picked by which would have forecast its last 12 months best. Every forecast shows its range, and you can change any month.
Insulated bottle, 750 ml, units a month
Solid: sold last year. Red: units it would have sold in September and October if it hadn’t sold out, which the forecast counts as demand. Dashed: the forecast, with the shaded range it expects to land in 9 months out of 10.
Every product’s forecast
| Product | Model | Next 30 days | Next 90 days | Accuracy | Your changes |
|---|---|---|---|---|---|
| Insulated bottle, 750 ml | Seasonal, peaks in December | 1,380 | 3,140 | 88.0% | +180 in January for your planned sale, added by you |
| Gift box set | Seasonal, peaks in November and December | 620 | 900 | 81.0% | – |
| Travel mug, black | Steady | 570 | 1,710 | 91.0% | – |
| Cold brew jar | Growing, up 4% a month | 250 | 790 | 84.0% | – |
| Spare bottle lid | Follows the bottle and its two bundles | 270 | 830 | 89.0% | – |
| Steel straw pack | Steady | 180 | 540 | 90.0% | – |
| Insulated bottle, 1 l | New, borrows the 750 ml bottle’s pattern | 0 | 640 | New | Launches 20 Jan, set by you |
Accuracy compares the last 3 months’ forecast with what sold. Your changes stay on the forecast, labelled, until you remove them.
Purchase orders
Every purchase order from draft to received. Expected dates use each supplier’s real lead time, not the date they quoted.
| Order | Status | Lines | Value | Supplier said | Expected | Next step |
|---|---|---|---|---|---|---|
| PO-124Ningbo Steelware | Draft | 840 bottles, 350 lids, 500 straw packs | $6,291 | – | 12 Jan | Approve and send today. |
| PO-125Jingdezhen Ceramics | Draft | 420 cold brew jars, 200 black mugs | $3,130 | – | 18 Jan | Approve by 8 Dec. |
| PO-123Leeds Print & Pack, sent 18 Nov | Confirmed | 650 gift box sets | $7,150 | 9 Dec | 9 Dec | On time. |
| PO-122Jingdezhen Ceramics, sent 30 Oct | Confirmed, late | 400 black mugs | $1,640 | 24 Nov | 10 Dec | 16 days late. Ask for a ship date. |
| PO-121Ningbo Steelware, sent 2 Nov | In transit, late | 200 bottles | $1,280 | 27 Nov | 10 Dec | At the port. The bottle’s buy list already counts it. |
| PO-119Ningbo Steelware, sent 20 Oct | Partly received, late | 200 of 500 straw packs still to come | $240 | 14 Nov | Not shipped | Short by 200. Chase them, or close the rest of the order. |
Drafts are ready to check and send as a PDF or email, in the supplier’s currency. Receive in part or in full; a short delivery stays open until you close it.
Suppliers
| Supplier | Quoted lead time | Real, last 3 orders | On time | Minimum order | Currency and terms |
|---|---|---|---|---|---|
| Ningbo Steelware | 25 days | 38 days | 1 of 3 | 300 per product | USD. 30% with the order, the rest before it ships |
| Jingdezhen Ceramics | 25 days | 41 days | 0 of 3 | 200 per product | CNY. 50% with the order, the rest before it ships |
| Leeds Print & Pack | 21 days | 21 days | 3 of 3 | 250 per product | GBP. 30 days after delivery |
The buy list plans with the real lead time. When a supplier speeds up, the next three orders bring the figure back down.
Locations
Stock and days of cover at each place you sell from. Each location is forecast from the orders it ships.
| Product | Own warehouse, New Jersey | ShipMonk, Las Vegas | Amazon FBA |
|---|---|---|---|
| Insulated bottle, 750 ml | 52040 days at 13 a day | 18026 days at 7 a day | 40040 days at 10 a day |
| Travel mug, black | 38048 days at 8 a day | 408 days at 5 a day | 16027 days at 6 a day |
| Cold brew jar | 30060 days at 5 a day | 11037 days at 3 a day | 0Not stocked |
Suggested transfers
| Product | Move | From | To | Freight | Why |
|---|---|---|---|---|---|
| Travel mug, black | 120 | Own warehouse, New Jersey | ShipMonk, Las Vegas | $46 | Las Vegas runs out in 8 days; New Jersey has 47. After the move both have about 32 days. |
| Insulated bottle, 750 ml | 70 | Own warehouse, New Jersey | ShipMonk, Las Vegas | $38 | Evens both sites to about 35 days, so west coast orders don’t ship from New Jersey at twice the postage. |
Approve a transfer and Kerno writes the transfer order, or the inbound shipment for ShipMonk. A transfer is suggested only when it costs less than ordering more.
Amazon FBA
Amazon FBA, from Amazon’s inventory, restock, inventory-planning and storage-capacity reports. Amazon’s own restock suggestion sits beside Kerno’s.
- Ready to ship674Units Amazon can sell now.
- Reserved96In customer orders, moving between warehouses, or being checked.
- To send this week90Units Kerno suggests sending from your own stock.
- Storage used182 of 300Cubic feet against your limit for standard-size items.
- Aged surcharge$168Amazon’s estimate for next month, on stock over 180 days old.
Send 90 black travel mugs to Amazon this week.Send 90 from New Jersey this week. Under 28 days, Amazon adds a low-inventory fee to every unit.
210 sage travel mugs are 271–365 days old.Amazon estimates a $168 surcharge next month. A removal order at about $0.97 a unit costs less, or run a coupon first.
Stock at Amazon
| Product | Ready to ship | Reserved | Unsellable | Amazon suggests | Kerno: send now | Next step |
|---|---|---|---|---|---|---|
| Insulated bottle, 750 mlB0C7K2M4QX | 340 | 6035 in orders, 20 moving | 4 | 280 | – | Covered to 14 Jan. Kerno plans the next send for 20 Dec, from the 12 Jan order. |
| Travel mug, blackB0C9TRVM6K | 130 | 3022 in orders, 8 moving | 2 | 180 | 90 | Send 90 from New Jersey this week. Under 28 days, Amazon adds a low-inventory fee to every unit. |
| Travel mug, sageB0C9TRVS2P | 204 | 62 in orders, 0 moving | – | – | – | Remove 150 or run a coupon before the aged surcharge rises in January. |
Amazon’s suggestion assumes you can send any amount at any time. Kerno’s counts what is in your own warehouse, what is on order from the supplier, and the next send date.
Units by age at Amazon
| Product | 0–90 days | 91–180 | 181–270 | 271–365 | Over 365 | Surcharge, next month |
|---|---|---|---|---|---|---|
| Insulated bottle, 750 ml | 400 | – | – | – | – | – |
| Travel mug, black | 150 | 10 | – | – | – | – |
| Travel mug, sage | – | – | – | 210 | – | $168 |
After this week’s send, storage use is 191 of 300 cubic feet. Inbound shipments are planned to avoid Amazon’s placement fee where splitting the shipment costs less than the fee.
Bundles
Bundles are built from stock of their parts, so Kerno forecasts each part from every listing it sells in.
| Bundle | Made from | Sold a day | Can build now | Limited by |
|---|---|---|---|---|
| Bottle and two spare lids | 1 × insulated bottle, 750 ml, 2 × spare bottle lid | 2 | 210 | Spare bottle lid |
| Starter set | 1 × insulated bottle, 750 ml, 1 × steel straw pack, 1 × spare bottle lid | 1 | 380 | Steel straw pack |
Where each part’s demand comes from
| Part | Sold on its own | In bottle and two spare lids | In starter set | Total a day |
|---|---|---|---|---|
| Insulated bottle, 750 ml | 27 | 2 | 1 | 30 |
| Spare bottle lid | 4 | 4 | 1 | 9 |
| Steel straw pack | 5 | – | 1 | 6 |
A spreadsheet that only counts lids sold on their own sees 4 a day and orders less than half of what you need.
Overstock
Stock with more than 180 days of cover, or nothing sold in 90 days. $5,240 at cost, kept off the buy list until it sells down.
| Product | Units | At cost | Sold a day | Days of cover | Last sold | Next step |
|---|---|---|---|---|---|---|
| Travel mug, sage$4.10 each | 640 | $2,624 | 0.4 | 1,600 | 21 Nov | Bundle it with the black mug, or mark it down 30%. It is off the buy list. |
| Bottle carry strap$1.10 each | 1,200 | $1,320 | 2 | 600 | 4 Dec | Add one free to bottle orders over $60 until it is under 180 days. |
| Cold brew jar, 2 l$7.20 each | 180 | $1,296 | – | No sales | 3 Aug | Ask the supplier about a return, or clear it at cost. |
The sage mug includes 210 units at Amazon, where it also costs an aged surcharge. See the Amazon FBA tab.
Budget
Your buying plan by month: stock arriving, what you pay and when (deposits included), against the budget you set.
| Month | Forecast sales | Stock arriving, at cost | Paid to suppliers | Budget | Left |
|---|---|---|---|---|---|
| December | $142,000 | $10,070 | $9,540 | $15,000 | $5,460 |
| January | $96,000 | $9,421 | $6,600 | $12,000 | $5,400 |
| February | $88,000 | $14,800 | $11,200 | $12,000 | $800 |
| March | $99,000 | $18,900 | $16,400 | $12,000 | −$4,400 |
| April | $103,000 | $12,300 | $10,900 | $12,000 | $1,100 |
| May | $108,000 | $11,700 | $11,000 | $12,000 | $1,000 |
March is $4,400 over budget.Spring stock for the 1 l bottle launch lands then. Move its second order to April, or raise March’s budget; the forecast shows what each choice does to stock.
Plan to a sales target
Set a target and Kerno shows the stock it takes. To reach $650,000 from December to May, 8% over the forecast, you’d buy about $8,400 more, mostly bottles and gift boxes, and pay $2,600 of it in March.
Overview
Shopify US and Amazon US together, in dollars. Each store has its own view in the P&L, and Amazon has its own tab.
- Net sales$158,750What customers paid for products, after discounts, promotions and refunds. Excludes tax and shipping charged.
- Net profit$10,513Net sales minus every cost: product, duties, shipping, fees, returns, ads and the operating costs you enter.
- Net margin6.6%Net profit ÷ net sales.
- Gross margin65.0%Net sales minus product cost, duties and inbound freight, divided by net sales.
- Contribution margin13.6%What sales leave after every cost of selling, including ads, before operating costs. Divided by net sales.
- Ad spend$35,600Spend across every connected ad account.
- MER (blended ROAS)4.46×Net sales ÷ ad spend, across all channels. It ignores which ad gets the credit.
- Break-even MER2.78×Net sales ÷ profit before ads. At this MER, ads use up all the profit before ads. Above it, there is profit left.
- POAS1.61×Profit before ads ÷ ad spend. Above 1×, the ads paid for themselves after every cost.
- Average order value$49.30Net sales ÷ orders.
- Orders3,220Orders placed in the period, on every store.
Where your revenue went
- Net sales$158,750
- Product cost−$47,164
- Duties and freight−$8,466
- Shipping and fulfilment−$25,557
- Fees−$17,402
- Returns−$3,000
- Ads−$35,600
- Contribution after ads$21,561
- Operating costs−$11,048
- Net profit$10,513
P&L
| Line | Shopify US | Amazon US | Total |
|---|---|---|---|
| Gross sales | $135,800 | $35,540 | $171,340 |
| Discounts and promotions | −$6,900 | −$640 | −$7,540 |
| Refunds | −$4,100 | −$950 | −$5,050 |
| Net sales | $124,800 | $33,950 | $158,750 |
| Product cost | −$37,600 | −$9,564 | −$47,164 |
| Duties and inbound freightAmazon: freight to Amazon’s warehouses | −$7,400 | −$1,066 | −$8,466 |
| Gross profit | $79,800 | $23,320 | $103,120 |
| Shipping and fulfilmentAmazon: FBA fulfilment fees | −$18,200 | −$7,357 | −$25,557 |
| Payment and referral fees | −$10,980 | −$5,217 | −$16,197 |
| Chargebacks | −$420 | — | −$420 |
| Storage and inventory fees | — | −$777 | −$777 |
| Coupons and selling plan | — | −$126 | −$126 |
| Return postage and unsellable units | −$3,000 | — | −$3,000 |
| Reimbursements | — | $118 | $118 |
| Ads | −$32,000 | −$3,600 | −$35,600 |
| Contribution | $15,200 | $6,361 | $21,561 |
| Rent | — | — | −$4,200 |
| Payroll | — | — | −$3,900 |
| Software | — | — | −$1,100 |
| Marketing | — | — | −$1,248 |
| Taxes paid | — | — | −$600 |
| Net profit | — | — | $10,513 |
| Sales tax collectedHeld for the tax office, not income. Amazon collects and pays its share itself. | $8,900 | $2,600 | $11,500 |
Products
By revenue, the gift box set looks like a winner.It’s your second-best seller.
By profit, it loses $4,400 a month.Duties, shipping surcharges, fees and returns take 37% of what it sells. Ads take another 41%.
| Product | Revenue | Product cost | Duties, tariffs and import tax | Shipping and carrier surcharges | Platform and payment fees | Returns | Ads | Profit |
|---|---|---|---|---|---|---|---|---|
 Insulated bottle, 750 ml | $48,200 | $14,300 | $2,900 | $5,600 | $4,300 | $900 | $14,100 | $6,100 |
 Gift box set | $31,500 | $11,400 | $2,600 | $4,900 | $2,900 | $1,300 | $12,800 | −$4,400 |
 Travel mug, black | $22,800 | $6,200 | $1,100 | $3,300 | $2,100 | $400 | $3,900 | $5,800 |
 Cold brew jar | $15,400 | $4,800 | $700 | $2,600 | $1,400 | $300 | $1,200 | $4,400 |
 Spare bottle lid | $6,900 | $900 | $100 | $1,800 | $700 | $100 | $0 | $3,300 |
Orders
Every order, on both stores, with its own costs. Sort it, filter it, or open one to see where each cost came from.
| Order | Store | Items | Sales | Landed cost | Shipping | Fees | Ads | Profit | Margin | Accuracy |
|---|---|---|---|---|---|---|---|---|---|---|
| #1042 | Shopify | 2 × Insulated bottle, 1 × Spare lid | $77.00 | −$25.65 | −$9.20 | −$2.53 | −$9.10 | $30.52 | 39.6% | Estimated |
| #1043 | Shopify | 1 × Gift box set | $64.00 | −$28.40 | −$17.90 | −$2.16 | −$21.40 | −$5.86 | -9.2% | Estimated |
| #1044 | Shopify | 3 × Travel mug | $84.00 | −$24.00 | −$9.40 | −$2.74 | $0.00 | $47.86 | 57.0% | Exact |
| 113-4826631-0927451 | Amazon | 1 × Insulated bottle | $32.00 | −$9.75 | −$6.12 | −$4.80 | −$3.40 | $7.93 | 24.8% | Exact |
| #1045 | Shopify | 1 × Cold brew jar | $30.00 | −$10.80 | −$8.60 | −$1.17 | −$2.30 | $7.13 | 23.8% | Exact |
| 113-9051174-3368260 | Amazon | 2 × Travel mug | $52.00 | −$14.20 | −$10.90 | −$7.80 | $0.00 | $19.10 | 36.7% | Estimated |
Order #1043 loses money: the gift box ships in the oversize carton, and its Meta ad cost a third of the sale.
Order #1042, on Shopify
2 × Insulated bottle, 750 ml, 1 × Spare bottle lid
| Line | Amount | Read from | Accuracy |
|---|---|---|---|
| Sales | $77.00 | The Shopify order | Exact |
| Product cost | −$21.40 | Purchase order PO-118, at the exchange rate on the day it arrived | Exact |
| Duties and freight | −$4.25 | Customs and freight bills on PO-118, split per unit | Exact |
| Postage | −$7.85 | The shipping label | Exact |
| Fuel and residential surcharges | −$1.35 | The carrier’s rates, until its invoice arrives | Estimated |
| Payment fee | −$2.53 | Shopify payout | Exact |
| Ad cost | −$9.10 | Meta, this order’s share of its campaign’s spend | Estimated |
| Profit on this order | $30.52 | Estimated lines become exact when the carrier invoice and the ad platform’s final figures arrive. | |
Customers
Shopify customers: 1,250 new and 440 returning this month. Lifetime value here is profit, after product cost, shipping, fees and returns, not revenue.
- Customers1,690People who ordered in the period, new and returning.
- Repeat purchase rate26.0%Share of customers in the period who had ordered before.
- Purchase frequency1.23Orders ÷ customers, in the period.
- New-customer cost (nCAC)$25.60Ad spend ÷ first-time customers.
- New-customer cost, fully loaded$26.60Ad spend plus the other marketing costs you enter ÷ first-time customers.
- aMER (new-customer MER)2.45×Net sales from first-time customers ÷ ad spend. Some tools call this new-customer ROAS.
- New-customer AOV$62.72Net sales from first-time customers ÷ first-time customers. aMER is this figure ÷ new-customer cost.
- Lifetime profit per customer$41.80Profit before ads from a customer’s first 12 months of orders, not their revenue. Projected from the cohorts that have had 12 months.
- LTV:CAC1.63×Lifetime profit per customer ÷ new-customer cost. Below 1×, a new customer never pays back what it cost to win them.
When each month’s new customers paid back
Profit per customer so far, by the month they first ordered. The marked cell is the month it passed what each customer cost to win.
| First order | nCAC | Month 0 | Month 1 | Month 2 | Month 3 | Month 4 | Month 5 |
|---|---|---|---|---|---|---|---|
| April | $24.10 | $17.80 | $22.40 | $25.90 | $28.70 | $31.20 | $33.40 |
| May | $25.30 | $18.20 | $22.90 | $26.10 | $29.00 | $31.40 | |
| June | $26.90 | $17.10 | $21.60 | $24.80 | $27.50 | ||
| July | $23.80 | $18.90 | $23.70 | $27.20 | |||
| August | $27.40 | $16.80 | $21.20 | ||||
| September | $25.60 | $17.40 |
New customers pay back in month 3 at the latest.So you can afford a higher new-customer cost on the campaigns that bring repeat buyers, and a lower one on those that don’t.
Marketing
Should you spend more?
- MER (blended ROAS)3.90×Net sales ÷ ad spend, across all channels. It ignores which ad gets the credit.
- MER, fully loaded3.75×Net sales ÷ ad spend plus the other marketing costs you enter, such as agency fees and content.
- Break-even MER2.64×Net sales ÷ profit before ads. At this MER, ads use up all the profit before ads. Above it, there is profit left.
- Allowable new-customer cost$28.40The profit before ads a new customer earns within your payback window. Pay more than this and that customer loses you money.
MER is 3.90× against a 2.64× break-even, yet new customers cost $25.60 in ads and earn $17.40 in their first month.Returning customers cover the gap, and earlier customers paid back by month 3. Judged over 4 months: scale with cash in view.
| Payback window | A new customer earns | Against $26.60 to win | Verdict |
|---|---|---|---|
| First month | $17.40 | −$9.20 | Hold prospecting |
| 3 months | $26.00 | −$0.60 | Hold prospecting |
| 4 months (this store) | $28.40 | $1.80 | Scale with cash in view |
| 12 months, projected | $41.80 | $15.20 | Scale with cash in view |
Shopify store, with agency and content costs in new-customer cost. A store whose customers rarely come back should judge by the first row. The scale check is added during early access.
Where the budget earns
Meta reports 3.40× ROAS. After every cost, its POAS is 0.85×.It loses $2,400 a month. Move budget to the campaigns and products that pay back, and check its new-customer cost before you cut.
By channel
| Channel | Ad spend | ROAS it reports | Sales from its orders | Profit after ads | POAS | New-customer cost |
|---|---|---|---|---|---|---|
| Google Ads | $13,500 | 4.30× | $52,600 | $8,400 | 1.62× | $25.96 |
| Meta | $15,800 | 3.40× | $41,100 | −$2,400 | 0.85× | $25.90 |
| Microsoft Ads | $2,700 | 3.89× | $9,800 | $900 | 1.33× | $30.00 |
By campaign, from the UTM tags on each order
| Campaign | UTM source / medium / campaign | Ad spend | Sales | Profit after ads | POAS | New customers |
|---|---|---|---|---|---|---|
| Google Ads: Shopping, all products | google / cpc / shopping-all | $9,800 | $38,900 | $6,300 | 1.64× | 410 |
| Google Ads: Search, brand name | google / cpc / search-brand | $3,700 | $13,700 | $2,100 | 1.57× | 110 |
| Meta: Prospecting, gift box video | facebook / paid / prospecting-giftbox | $11,200 | $26,300 | −$3,300 | 0.71× | 520 |
| Meta: Retargeting, cart viewers | facebook / paid / retargeting-cart | $4,600 | $14,800 | $900 | 1.20× | 90 |
| Microsoft Ads: Shopping, all products | bing / cpc / shopping-all | $2,700 | $9,800 | $900 | 1.33× | 90 |
| Email: Weekly newsletter and flows | klaviyo / email / * | $0 | $8,400 | $3,900 | — | 30 |
| No tag (search, direct) | — | $0 | $12,900 | $4,400 | — | — |
Shopify store. Amazon Ads sit on the Amazon tab, by product, because Amazon doesn’t share who its customers are.
Amazon
Amazon US, sold through FBA. Read from Amazon’s order, settlement, fee and FBA inventory reports and the Amazon Ads API.
- Net sales$33,950What customers paid for products, after discounts, promotions and refunds. Excludes tax and shipping charged.
- Contribution margin18.7%What sales leave after every cost of selling, including ads, before operating costs. Divided by net sales.
- Amazon fees37.6%Referral, FBA, storage, placement and other Amazon fees, less reimbursements, as a share of Amazon sales.
- TACoS10.1%Amazon ad spend ÷ all Amazon sales, from ads or not. Falling TACoS means more sales arrive without ads.
- Refund rate2.6%Units refunded ÷ units sold.
The travel mug, black has 19 days of FBA stock left, with nothing on the way.Under 28 days, Amazon adds a low-inventory-level fee to every unit it ships. Send an inbound shipment this week, or reorder from the supplier if the warehouse can’t cover it.
The cold brew jar has 68 days of stock at Amazon.Its oldest units turn 181 days old next month, when the aged inventory surcharge starts. A coupon or a removal order costs less than the surcharge.
Profit by ASIN
| Product | Units | Sales | Refunds | Referral fees | FBA fees | Landed cost | Freight to Amazon | Sponsored ads | ACoS | Profit | FBA stock |
|---|---|---|---|---|---|---|---|---|---|---|---|
| Insulated bottle, 750 mlB0C7K2M4QX | 620 | $19,840 | −$576 | −$2,907 | −$3,794 | −$5,518 | −$527 | −$2,100 | 22.3% | $4,418 | 940 on hand, 600 inbound45 days |
| Travel mug, blackB0C9TRVM6K | 410 | $10,660 | −$234 | −$1,571 | −$2,234 | −$2,624 | −$287 | −$900 | 22.0% | $2,810 | 260 on hand19 days |
| Cold brew jarB0CBJR2C8W | 180 | $5,040 | −$140 | −$739 | −$1,328 | −$1,422 | −$252 | −$600 | 46.2% | $558 | 410 on hand68 days |
FBA fee per unit: insulated bottle $6.12, travel mug $5.45, cold brew jar $7.38, from Amazon’s fee for each size tier. Referral fees are 15% of the price, less what Amazon credits back on refunds. Ad-attributed sales give a blended ACoS of 24.3%, ROAS 4.11×.
Charged to the account, not to one order
| Line | Amount | Read from | Accuracy |
|---|---|---|---|
| Promotions | −$640 | Settlement report, promotion rebates | Exact |
| Monthly storage | −$412 | FBA storage fee report | Estimated |
| Aged inventory surcharge | −$96 | FBA aged inventory surcharge report | Exact |
| Inbound placement fee | −$238 | Shipment fees on inbound plan FBA18K4QZ | Exact |
| Low-inventory-level fee | −$31 | Settlement report, per unit shipped while the mug ran low | Exact |
| Coupon fees | −$86 | Settlement report, coupon redemptions | Exact |
| Professional selling plan | −$40 | Settlement report, subscription fee | Exact |
| Reimbursements, lost and damaged units | $118 | FBA reimbursements report | Exact |
Profit by ASIN is before these lines; the P&L and the Overview include them. Fees on orders that haven’t settled yet use Amazon’s fee preview, then switch to the settled figure. Amazon doesn’t share who its customers are, so new-customer figures cover Shopify only.
Costs
Costs you add
The costs no bill per order carries. Enter each once; Kerno repeats it, spreads it, or works it out as a share of something else.
| Cost | Category | How it repeats | This month |
|---|---|---|---|
| Warehouse rent | Rent | Monthly | −$4,200 |
| Part-time packer | Payroll | Monthly | −$3,900 |
| Klaviyo, Gorgias and other apps | Software | Monthly | −$1,100 |
| Ads agency | Marketing | 6% of Meta spend | −$948 |
| Product photo shoot | Marketing | One-off $1,800, spread over 6 months | −$300 |
| Income tax instalment | Taxes paid | Quarterly, spread monthly | −$600 |
Where every figure comes from
Every figure says where it came from. A cost Kerno can’t read yet shows as missing or estimated, never as zero.
Read from day one of early access
- Shopify
- Sales, discounts, refunds, chargebacks and Shopify Payments fees, exact from the payout. Return reasons, dispute reasons and stock by location, by product.
- Your purchase orders
- Product cost per unit, with duties, freight and the exchange rate on the day stock arrived. The date each supplier promised, so a late order shows before you run out.
- Shipping labels
- Postage per order, from Kerno, ShipStation and EasyPost labels.
- Google Ads and Meta
- Ad spend by campaign, and by product for Google Shopping.
Added during early access
- Your 3PL
- Stock counts and receipts from ShipMonk, ShipBob and other 3PLs, checked against what you sent and sold, so missing units show at cost.
- Carrier invoices
- Fuel, residential, oversize and peak surcharges, matched to each package. Estimated until the invoice arrives.
- Amazon Seller Central
- Orders, refunds, referral and FBA fees, storage and placement fees, reimbursements and FBA stock, from Amazon’s settlement and fee reports.
- Amazon Ads, TikTok and Microsoft Ads
- Ad spend for the rest of your channels, by campaign and, on Amazon, by product.
- PayPal and Stripe
- Payment fees and chargebacks outside Shopify Payments.
- Costs you enter
- Rent, wages, software, agency fees and taxes paid: monthly, one-off or a percentage of something else, in your own categories.
- Exact Read from the bill or payout itself.
- Estimated Worked out until the final figure arrives, then replaced.
- Missing Not connected yet. Totals that depend on it say so.
Grow what already sells.
Pick a product and try a move: a bundle, an add-on at checkout, a discount for a campaign. Kerno works out what it earns, the stock it needs and the date to order by, and says so when a move loses money.
Growth moves
Example store
Insulated bottle, 750 ml sells 1,380 a month
486 bundles a month at 10% off +$1,394 profit a month
Bought together in 22% of orders today. One parcel saves the second postage.
Needs 182 more spare bottle lids a month: add them to the order due 6 Dec.
110 added at checkout a month, at $6 +$475 profit a month
Clears the 1,200 straps in stock in 7 months, not 20.
1,030 more insulated bottles sold over 28 days +$4,177 profit over the 28 days
Past 15% discounts sold 1.8 times the usual rate. Stock for it: order 2,318 by 21 Apr.
Profit is after product cost, duties, postage, fees and returns, before ads. Rates come from this store’s own orders and past campaigns.
Compared with Brightpearl, Cin7 and Finale Inventory.
The whole flow, stage by stage.
| Stage | Kerno | Brightpearl | Cin7 | Finale Inventory |
|---|---|---|---|---|
| Getting started | Runs alongside what you use now, and sets itself up from your history | Scoped before you sign; customers “go live in 90-120 days, on average” | Group, one-to-one or partner-led onboarding; fee and time not published | “Go live in 2–6 weeks”; standard onboarding included |
| Purchase orders | Drafted from the forecast, in the factory’s currency. Confirm it, or autosend | Suggested purchase orders through Inventory Planner | From reorder suggestions with the ForesightAI add-on; foreign currencies converted | Recommended reorder quantities turned into purchase orders |
| Production and shipments | Production status on every PO; packing list and commercial invoice in one click | Not documented | Stock in transit for invoiced POs not yet received; production tracking not documented | Several shipments per PO; production tracking not documented |
| Landed cost | Freight and duties on the shipment, added to each product’s cost from the bills | Freight and import duty in each product’s landed cost | Extra PO costs spread into landed cost | PO fees spread by quantity, weight, value or volume |
| Receiving | Counted in against the PO at any warehouse; shorts and damage flagged on the spot | Not documented | Partial receipts; the shortfall stays on backorder | Partial receipts, the rest backordered; scanner receiving is an add-on |
| Builds and kits | See what you can build today; each build booked at its full cost | Bundles, kits and assemblies; bills of materials through a partner app | Bills of materials and assembly on every plan; MRP on Core Pro and up | Kits, bundles and bills of materials; builds use up components |
| Orders and stock | Shopify, Amazon and wholesale in one list; stock held for each order as it arrives | Shopify and Amazon; orders allocated across channels and warehouses | Shopify and Amazon; Core allocates stock when the order comes in | Shopify and Amazon, including FBA; several warehouses |
| Shipping | Labels, packing lists and customs invoices; tracking to the customer and channel | Courier labels from the order; ShipStation also connects | Through ShipStation and other shipping apps | Labels through a free ShipRush account; ShipStation also connects |
| Accounting | Invoices, cost of goods and supplier bills sync to QuickBooks Online or Xero | Its own built-in accounts, or Xero, QuickBooks Online or Sage Intacct | Xero or QuickBooks Online, including cost of goods | QuickBooks Online: invoices, bills and cost of goods |
| Contract | No card, no contract. Export everything as CSV whenever you like | Not documented | Core monthly or yearly, renews automatically, 30 days’ notice to leave | Most sign 12, 24 or 36 months; renews automatically, 30 days’ notice |
| Price | Free during early access, then a founding price you keep | By quote; unlimited users included | Core $349–$1,199 a month; Omni by quote | From $499 a month; Enterprise by quote |
From each vendor’s website, help centre, pricing page and Shopify App Store listing, checked October and November 2026. “Not documented” means their pages don’t describe it.
Start with one part. Grow into the rest.
Kerno Forecast decides what to buy. Kerno Insights shows what it earned. Nothing to rip out: both connect alongside the tools you already run.
| Kerno Forecast | Kerno Insights | |
|---|---|---|
| Answers | What should I order, and when? | What does each product really earn, and what is eating it? |
| Looks | Forward: every product’s orders for the next 12 months | Back: every order, cost and fee so far |
| Gives you | A buy list and draft purchase orders, with the reason behind every quantity | Profit per product and per order, and alerts with the next step |
| Changes anything? | Drafts purchase orders to confirm, or autosends them | No. Read-only: your systems stay in charge |
| For | Whoever buys the stock | The owner and the finance lead |
Pick a starting point
Connect Shopify or Amazon to either one and see your own numbers.
Add the other
Both run on the same connections, so what sells, what earns and what to reorder sit in one place.
Run everything on Kerno
When you're ready, Kerno can run stock, orders, purchasing and fulfilment too. Your products, suppliers and history carry over.
Tell us what you run today.
- Kerno
- More profit
- More to spend on marketing
- More sales
- Less stress
- More time at the beach
If you like beaches.
Talk to usWe read every request ourselves, and you talk to the people who built it.
