How do you calculate scrap rate?

Divide scrap units by total units produced and multiply by 100. With 30 scrap units out of 1,000 produced, that's 30 ÷ 1,000 × 100 = 3% scrap rate.

What does a negative gap to target mean?

A negative gap means you're over target. In the example, a 2% target minus a 3% actual gives −1 point, so the line is running 1 percentage point above its allowed scrap and needs corrective action.

What is a good scrap rate in manufacturing?

It varies by industry, but many discrete-manufacturing lines aim for 1–2% and consider anything above 5% a problem. The right benchmark is your own target — here, a 3% actual against a 2% target is off-pace.

How does scrap affect OEE?

Scrap reduces the Quality factor of OEE: only good, first-pass units count toward Quality. A 3% scrap rate caps your Quality score at about 97%, before any rework is considered.

Is scrap rate the same as yield?

They're complementary. First-pass yield is the percentage of good units; scrap rate is the portion lost. A 3% scrap rate roughly corresponds to a 97% yield if there's no rework in between.

Should rework be counted as scrap?

No — scrap is product that can't be recovered. Reworked parts are salvaged and don't count as scrap, but they still hurt first-pass yield and labor cost, so track them separately.

OEE & Factory Performance calculator

Scrap Impact on OEE Calculator

Scrap rate is the percentage of units a process produces that can't be sold or reworked into good product, and it's the headline driver of the Quality pillar in OEE. Quality engineers, line supervisors, and CI teams track it because scrap is a triple loss — wasted material, wasted machine time, and wasted labor — all baked into a part that ships to the dumpster. This calculator returns both the scrap rate and the gap between that rate and your target, so you instantly know whether the line is inside or outside its quality envelope. Knowing the gap, not just the rate, is what turns a number into an action.

What this calculator does

Calculate scrap rate for OEE & Factory Performance: scrapped units as a share of total units produced.
Use it to track scrap rate against target in OEE & Factory Performance.
It divides scrap units by total units produced to give a scrap rate as a percentage, then subtracts that rate from your target to show the gap in percentage points.

Formula used

Scrap rate = scrap units ÷ total units produced × 100
Gap to target = target scrap rate − scrap rate

Inputs explained

Scrap units: Scrap units in the period — the numerator.
Total units produced: Total units produced in the same period — the denominator.
Target scrap rate: Your target, used to show the gap.

How to use the result

Use it at end-of-shift or end-of-run when you have a confirmed scrap count and total output, and you want to grade quality against a target before a production review.
Scrap rate alone doesn't distinguish a few catastrophic defects from many minor ones, and it excludes rework — parts that were salvaged still consumed time and may belong in a separate yield analysis.

Current U.S. benchmarks

U.S. manufacturing runs at 75.6% of capacity (Federal Reserve, May 2026). New factory orders are up 2.3% year over year (Census).

Common questions

How do you calculate scrap rate? Divide scrap units by total units produced and multiply by 100. With 30 scrap units out of 1,000 produced, that's 30 ÷ 1,000 × 100 = 3% scrap rate.
What does a negative gap to target mean? A negative gap means you're over target. In the example, a 2% target minus a 3% actual gives −1 point, so the line is running 1 percentage point above its allowed scrap and needs corrective action.
What is a good scrap rate in manufacturing? It varies by industry, but many discrete-manufacturing lines aim for 1–2% and consider anything above 5% a problem. The right benchmark is your own target — here, a 3% actual against a 2% target is off-pace.
How does scrap affect OEE? Scrap reduces the Quality factor of OEE: only good, first-pass units count toward Quality. A 3% scrap rate caps your Quality score at about 97%, before any rework is considered.
Is scrap rate the same as yield? They're complementary. First-pass yield is the percentage of good units; scrap rate is the portion lost. A 3% scrap rate roughly corresponds to a 97% yield if there's no rework in between.

Last reviewed 2026-05-12.