The percentage of units that pass a defined process the first time, without rework, repair, or retest.
First pass yield indicates process health by showing how much output is right the first time.
Low stability or weak process capability often drives first-pass losses.
Calculate first pass yield
Divide the units that pass the first time by the units entering the defined process, then multiply by 100%. For example, 920 of 1,000 units passing first time gives 92%. State the process and reporting period.
Improvement levers
Teams improve FPY through setup control, better work instructions, defect-proofing, and faster feedback loops.
Monitoring SPC signals helps teams intervene before defects multiply.
Do not count units that passed after rework as first-pass successes. Final yield can be high while first pass yield remains low.
Key takeaways
- First pass yield measures process effectiveness at source.
- Higher FPY lowers cost and improves delivery confidence.