Quality / WORKSHEET 04

First-pass yield calculator

Measure the share of units that meet requirements the first time, without repair, rework, retest, or rerouting.

Output: First-pass yield, first-pass defect rate, and first-pass defect count.
Processing: In this browser only
Cost: Free · no account

LIVE WORKSHEET

Reconcile first-pass output

Runs locally

Inputs and results stay in this browser. Verify important outputs independently.

APPLICATION NOTES

Use the result on the floor

Calculate first-pass yield and first-pass defects from units entering a process and units accepted without rework. Keep the input boundary, unit definitions, and time period attached to any recorded result so another person can reproduce it.

Useful for

Track hidden rework separately from final yield.
Compare quality performance by process step.
Establish a baseline before defect reduction work.

MODEL BOUNDARY

Assumptions and limitations

Assumptions

Every entered unit receives one first-pass disposition.
Accepted units exclude anything reworked or retested.
Both counts use the same process boundary and time period.

Limitations

FPY does not describe defect severity or where a defect originated.
Final yield may be higher after rework and should not be substituted for FPY.

DECISION CHECK

Verify before changing the process

Use approved inspection and disposition records for product release. This calculator does not determine conformance or replace a quality management system.

REFERENCE

Frequently asked questions

What counts as a first-pass good unit?

A unit accepted without rework, repair, retest, or another corrective loop inside the chosen process boundary.

Can FPY be lower than final yield?

Yes. Final yield may include units recovered through rework; FPY intentionally exposes that hidden factory work.