first pass yield formula

First Pass Yield (FPY) is a key performance indicator (KPI) used in manufacturing and quality control to measure the effectiveness of a manufacturing process. It calculates the percentage of products or components that pass all quality inspections and tests on the first attempt without any rework or repair. A high FPY indicates an efficient and reliable production process, while a low FPY suggests that a significant portion of products require rework or are rejected.

Many manufacturers are considering Total yield as first pass yield, what is not correct. On this article we’ll analyse the first pass yield formula.

The formula for First Pass Yield (FPY) is:



  • Good Units Produced: This represents the number of products or components that meet all quality criteria and pass all inspections during the first attempt without the need for rework or repair.
  • Total Units Started: This is the total number of products or components that entered the manufacturing process, including those that passed, those that failed and required rework, and any scrapped items.

The result is usually expressed as a percentage.

Here’s an example to illustrate how to calculate FPY:

Let’s say a manufacturing process starts with 1,000 units, and after all inspections and tests, 800 units meet all quality criteria without any rework or repair required.



In this example, the First Pass Yield for the manufacturing process is 80%, meaning that 80% of the units produced passed all inspections and tests on the first attempt.

Monitoring FPY is essential in manufacturing as it helps identify areas of improvement in the production process, reduces waste, and enhances product quality. A higher FPY generally indicates better process efficiency and reduced production costs.