First Pass Yield
FPYThe percentage of units that pass through a process step correctly on the first attempt, without rework or rejection.
Also known as: First Run Yield (FRY), First Time Right, First Time Yield, Right First Time Rate
First Pass Yield measures the quality of a process step. A 95% FPY means 95 out of 100 units are completed correctly the first time. The remaining 5 either need rework (sent back through earlier steps) or are scrapped entirely.
FPY is the complement of the reject rate: FPY = 1 − Reject Rate.
Formula
FPY = (Total units − Rejected units) / Total units × 100%
Or equivalently: FPY = 1 − Reject Rate
Example
A data entry process handles 200 forms per day. 16 forms contain errors and must be corrected. FPY = (200 − 16) / 200 = 92%. Reject rate = 16 / 200 = 8%.
Why It Matters
Rework is expensive, it consumes capacity at every step the unit passes through again. A step with 10% rework doesn’t just lose 10% of its own capacity; it also loads earlier steps that must redo the work. Even small rework rates can significantly increase flow times and reduce effective capacity, especially at or near the bottleneck.