What is First Pass Yield (FPY)?
A guide to First Pass Yield — what it is, why it matters, and how to calculate it for your factory.
What is First Pass Yield?
First Pass Yield (FPY), also called First Time Right (FTR), is the percentage of units produced that meet quality requirements the first time through a process — without any rework, repair or rejection. It is one of the most important quality metrics in manufacturing because it measures the true capability of your production process.
FPY Formula
Example: 1,000 units produced. 35 rejected. 20 of those were reworked and passed. 15 were scrapped.
FPY vs Overall Yield
Overall yield counts reworked units as good output. FPY does not — it exposes the hidden rework cost that overall yield conceals. A factory might report 98% overall yield but only 85% FPY — the 13% gap represents rework burden on labour, machines and materials.
Rolled Throughput Yield (RTY)
For multi-station production lines, multiply each station's FPY together to get RTY:
How to Improve FPY
- Implement incoming quality control — defective material causes downstream FPY loss
- Use Standard Operating Procedures (SOPs) and visual work instructions at each station
- Perform Process Capability studies (Cpk) on critical dimensions
- Track defect types by Pareto analysis — fix the top 2–3 defect types first
- Implement mistake-proofing (poka-yoke) at high-defect stations
- Analyse FPY by shift, machine and operator to find root causes
FPY Benchmarks
| FPY % | Rating |
|---|---|
| Below 90% | Poor — high rework burden |
| 90–95% | Average — industry typical |
| 95–99% | Good — well-controlled process |
| Above 99% | World class |