About the Fill Rate Calculator
This fill rate calculator measures how completely you ship what customers order, at three levels of detail. Order fill rate is the share of orders shipped complete; line fill rate is the share of order lines shipped in full; and unit (or case) fill rate is the share of individual units shipped. It also combines order fill with on-time delivery, damage-free delivery and documentation accuracy to give the perfect order rate.
Distribution centres, 3PLs, e-commerce sellers and suppliers reporting to retailer scorecards use these metrics to track service level, spot chronic short-shipping and quantify backorders. Because each level is stricter than the last, unit fill rate is almost always the highest and perfect order rate the lowest — seeing them side by side shows where service breaks down.
Enter counts from your WMS or order system for the same period. The perfect order rate here multiplies the component percentages, the common approach used in supply-chain benchmarking, which assumes the failures are roughly independent.
With the default inputs, the order fill rate is 92%. Change any value above to recalculate instantly.
How to use the fill rate calculator
- 1Pick a period and pull totals from your order or warehouse system.
- 2Enter total orders and how many shipped complete.
- 3Enter total order lines and lines shipped in full.
- 4Enter units ordered and units shipped.
- 5Add on-time, damage-free and documentation percentages to get the perfect order rate.
Formula and method
Each fill rate divides what was shipped in full by what was ordered, at a different level: whole orders, individual lines (SKU rows on an order) or units/cases. An order with ten lines counts as unfilled at the order level if even one line is short, which is why order fill is the strictest of the three.
Perfect order rate multiplies the order fill rate by the percentage of orders delivered on time, without damage and with correct documentation. Multiplying the percentages assumes the failures are independent; if you can count perfect orders directly from your system, that exact count is more accurate.
- Order fill
- Share of orders shipped 100% complete
- Line fill
- Share of order lines shipped in full
- Unit fill
- Share of units or cases shipped
Worked examples
Distribution centre monthly scorecard
1,104 of 1,200 orders shipped complete (92%), 5,238 of 5,400 lines (97%) and 47,040 of 48,000 units (98%). Multiplying 92% × 96% on time × 99.5% damage-free × 99% correct documents gives a perfect order rate of about 87%.
E-commerce seller with stockouts
Order fill is 774 ÷ 860 = 90%, line fill 1,634 ÷ 1,720 = 95% and unit fill 2,494 ÷ 2,580 = 96.7%. With 93% on time and 98% damage-free, the perfect order rate is 0.90 × 0.93 × 0.98 × 1.00 = 82%.
Frequently asked questions
How do you calculate fill rate?+
Divide what you shipped by what was ordered. Unit fill rate = units shipped ÷ units ordered × 100; line fill rate uses order lines shipped in full; order fill rate uses orders shipped complete. Use the same period and exclude cancelled orders from both counts.
What is a good fill rate?+
Many retailers expect suppliers to hit 95%–98% unit or case fill rate, and some scorecards charge penalties below about 95%. Order fill rates are naturally lower than unit fill rates, especially for orders with many lines.
What is the difference between fill rate and perfect order rate?+
Fill rate only checks quantity. Perfect order rate also requires the order to arrive on time, undamaged and with correct paperwork, so it is always equal to or lower than the order fill rate.
Why is my order fill rate so much lower than my unit fill rate?+
One short line makes the whole order incomplete. An order with 20 lines at 98% line fill has only about a 67% chance of shipping complete (0.98²⁰), so large multi-line orders drag order fill down.
Is fill rate the same as service level?+
They are related but not identical. Cycle service level is the probability of not stocking out during a replenishment cycle; fill rate is the fraction of demand actually met from stock. A high service level usually implies a high fill rate, but the numbers differ.