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First Pass Yield Calculator

Work out first pass yield instantly with clear inputs, formula shown and shareable results.

About First Pass Yield Calculator

First pass yield counts only units that come through right the first time. Because sequential steps compound, rolled throughput yield is the per-step yield raised to the number of steps — which is why a line of ten 97% operations delivers barely 74% clean output.

Formulas

First pass yield

FPY % = Units passing first time / Units entering x 100

Rolled throughput yield

RTY = FPY ^ Number of steps

Worked example

With the default values below, First Pass Yield Calculator returns First pass yield of 93.00%. Change any input above and every figure here is recalculated in your browser.

Inputs used

Units entering the process
2,000
Units passing without rework or scrap
1,860
Sequential process steps
6

Results

First pass yield
93.00%
Rolled throughput yield across all steps
64.70%
Units needing rework or scrap
140
Normalised yield per step
93.00%

Step by step

  1. 1Values used
  2. 2First pass yield
  3. 3Rolled throughput yield
  4. 4First pass yield= 93.00
  5. 5Rolled throughput yield across all steps= 64.70
  6. 6Units needing rework or scrap= 140
  7. 7Normalised yield per step= 93.00

Assumptions and limits

  • The result is derived only from the 3 inputs listed above. Anything not among them is not part of the calculation.
  • In particular, this calculator does not take inflation, tax, fees or charges or compounding frequency into account.
  • Figures are rounded for display to 2 decimal places, so totals built from several rounded parts can differ slightly from the unrounded arithmetic.
  • This is an estimate for general information and not professional financial, tax or legal advice. See the full disclaimer for the limits that apply to this kind of calculator.

How these calculators are built and tested is described on the Methodology page. If a figure looks wrong, please report it.

Frequently Asked Questions

What is the hidden factory?

The capacity consumed by inspection, rework and retest that never appears in the output figures. FPY is the standard way to make it visible.

Should scrap and rework both count against FPY?

Yes. Any unit that did not pass cleanly the first time fails FPY, regardless of whether it was later rescued.

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First Pass Yield Calculator – Calculate First pass yield