Every wrong item shipped costs twice: the return shipping and the customer who does not come back. Order fulfilment accuracy — the share of orders picked, packed and delivered exactly as ordered — is the quality metric behind returns, refunds and reviews for any business that ships or delivers. This calculator computes order accuracy and error rate from your order counts, breaks errors down by type (wrong item, wrong quantity, damaged, missing, wrong address), and estimates what each error costs, so you know which fix pays first.
The formula
Order accuracy = Orders fulfilled without error ÷ Total orders × 100.
A seller shipped 1,400 orders last month; 63 had an issue — 21 wrong item, 12 wrong quantity, 18 damaged, 7 missing item, 5 wrong address → accuracy 95.5%, error rate 4.5%. If each error costs about ₹180 in reverse shipping, re-ship and handling, that is ₹11,300 a month before lost customers.
How to use the calculator
- Enter total orders and the number with errors (or enter errors by type).
- Enter an average cost per error — reverse shipping plus re-shipment plus staff time — and optionally the refund/credit given.
- Read accuracy, error rate, errors per 1,000 orders, and the monthly cost of errors by type.
- Track weekly; add the previous periods to see the trend after a process change.
- Combine with on-time delivery for the "perfect order" rate — on time, complete, undamaged, correctly invoiced.
Where errors come from, and the fixes
| Error | Usual cause | Fix |
|---|---|---|
| Wrong item | Similar SKUs, no scan at pack | Barcode every SKU (barcode generator) and scan-to-verify with the scanner |
| Wrong quantity | Counting by eye, bulk orders | Pick lists with quantities; weigh the packed parcel against expected weight |
| Damaged | Under-packing, wrong box | Right-size boxes; the volumetric weight calculator shows size trade-offs |
| Missing item | Multi-item orders packed in stages | Pack one order at a time; tick the list on the shipping label |
| Wrong address | Copy-paste from chats | Confirm PIN code and phone on WhatsApp before dispatch |
| Wrong invoice | Manual invoicing | Generate the GST invoice from the order, not from memory |
Marketplaces track seller defect rates and suppress listings above thresholds (typically 1–2% for order defects); your own accuracy number will usually be the first warning.
Benchmarks
Well-run small warehouses reach 99%+; 97–99% is common for small sellers packing by hand; below 95% signals a process problem rather than bad luck. Each point of accuracy on 1,000 orders is 10 fewer returns.
Barcode choices for SKUs — when a free code is enough and when you need GS1 — are explained in Barcodes for your products, and the marketplace defect thresholds in Pricing for Amazon, Flipkart and Meesho.
Related tools
- On-time delivery rate — the other half of the perfect order.
- Defect rate calculator — product quality upstream of packing.
- Inventory turnover — stock accuracy feeds order accuracy.
- Shipping label generator — labels with order contents listed.
- CSAT calculator — satisfaction after delivery.