Free tool
Scrap rate calculator
What share of output never made it out the door as a good part.
Scrap rate is one input into the Quality component of OEE. Track it alongside First Pass Yield — scrap counts what never made it, FPY counts what made it right the first time, and they usually move together.
How the calculation works
Scrap rate= scrap or rejected quantity ÷ total quantity produced, expressed as a percentage. It’s the most direct read on how much of your output is being thrown away rather than shipped or moved forward.
Scrap rate is a subset of the story First Pass Yield tells — FPY also accounts for units that needed rework but weren’t scrapped outright. A plant can have a low scrap rate and still have a quality problem if a lot of parts are passing only after rework.
Scrap rate directly determines the Quality component of OEE (good parts ÷ total parts is just 1 − scrap rate, when rework isn’t a factor) — a rising scrap rate is one of the three places OEE can be quietly losing capacity.
This calculator is for one run entered by hand. ThingConnect tracks good/scrap counts continuously from controller and inspection data, so a scrap-rate spike on one shift or one part number shows up immediately instead of at end-of-month reconciliation.