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Order Fill Rate Calculator
Measure the percentage of customer orders fulfilled completely from available stock on the first shipment. Find gaps in inventory availability.
What does this calculator measure?
Order fill rate is the percentage of orders filled completely on the first shipment from available inventory. An order with any missing or backordered item does not count as completely filled, even when the remaining items ship later.
Enter your figures
Use one consistent period. Calculations run locally in your browser.
Orders evaluated during one period using a consistent cancellation policy.
Orders fulfilled in full on the first shipment, without backorders.
Your result
Fill in all fields or load the worked example to see your result.
Put your figures to work
Track available stock and review reorder levels for the products causing incomplete orders.
Start managing inventoryFormula and worked example
Order fill rate (%) = Completely filled orders ÷ Total orders × 100
If 225 of 250 orders shipped completely on the first shipment, order fill rate is 225 ÷ 250 × 100 = 90%. The other 25 orders were not completely filled.
How to use the calculator
- Choose the product, category or business and the period you want to review.
- Enter the figures described beside each field using consistent units.
- Review the result alongside the assumptions below before changing purchasing or stock plans.
How to interpret your result
Review the missing SKUs behind incomplete orders. This order-level metric treats every order equally regardless of size. It does not measure delivery punctuality: an order can be fully filled yet arrive late. Compare results using a consistent measurement window and fulfillment policy.
Explore the inventory workflow in My Inventory ItemsFrequently asked questions
What is the difference between order fill rate and unit fill rate?
Order fill rate counts fully fulfilled orders. Unit fill rate counts units supplied out of units requested. Shipping 9 of 10 units gives a 90% unit fill rate but does not make that order completely filled.
Do backorders count as filled orders?
Not for this first-shipment definition. Orders completed later remain incomplete in the original first-shipment measurement.
Is fill rate the same as OTIF?
No. OTIF means on time and in full, so it includes a timing requirement. This calculator checks complete fulfillment without evaluating delivery dates.