Why spread scrap cost across all produced parts?

The batch paid for the scrapped parts as well as the good ones, so every part made helps carry the loss. Dividing by produced parts gives the figure a part price can recover.

Why not divide by the scrapped parts alone?

That answers what one failure cost, not what the batch carries. The produced-part basis is the one that belongs in the part price because good parts pay for bad ones.

What goes into containment and investigation cost?

The labor and material spent containing the defect: sorting, quarantine, inspection, and root-cause work. Routine production inspection belongs elsewhere.

Does the per-part scrap cost fall as the batch grows?

Yes. The scrapped count and the adders stay fixed while produced parts rise, so each part carries a smaller share. A larger batch genuinely lowers the cost per produced part.

CNC Machining calculator

Scrap From Machining Calculator

Add what scrapped parts cost a batch, including containment and rework charges. Enter the scrapped count, the value of each scrapped part, the adders, and the batch population.

What this calculator does

Total scrap cost for a batch, split into scrapped part value and containment or rework adders, spread over produced parts.

Formula used

Scrapped part value = scrapped parts × cost per scrapped part
Containment, rework, and disposal adders = containment and investigation cost + rework, remake, and disposal burden
Total machining scrap cost = scrapped part value + containment, rework, and disposal adders
Scrap cost per produced part = total machining scrap cost ÷ parts produced in batch
Scrap rate = scrapped parts ÷ parts produced in batch × 100

Inputs explained

Scrapped Parts: Parts scrapped out of this batch.
Cost per Scrapped Part: Material and labor already sunk in each scrapped part.
Containment and Investigation Cost: Cost to contain the defect and find its cause.
Rework, Remake, and Disposal Burden: Extra work, remake, and disposal cost for the batch.
Parts Produced in Batch: All parts started in the batch.
Target Scrap Rate: Scrap rate the process should stay under.

How to use the result

Best suited to costing a quality escape, setting a scrap target, comparing process options.
Lost margin on scrapped parts is not included. Late-delivery disruption sits outside this number.

Current U.S. benchmarks

The producer price index for steel mill products stands at 381.162 (BLS, Aug 2026), up 23.4% from a year earlier. Quotes priced off last quarter's material cost miss this move.
The U.S. has 17,154 machine shops establishments employing about 223,303 workers (Census County Business Patterns, 2023).

Common questions

Why spread scrap cost across all produced parts? The batch paid for the scrapped parts as well as the good ones, so every part made helps carry the loss. Dividing by produced parts gives the figure a part price can recover.
Why not divide by the scrapped parts alone? That answers what one failure cost, not what the batch carries. The produced-part basis is the one that belongs in the part price because good parts pay for bad ones.
What goes into containment and investigation cost? The labor and material spent containing the defect: sorting, quarantine, inspection, and root-cause work. Routine production inspection belongs elsewhere.
Does the per-part scrap cost fall as the batch grows? Yes. The scrapped count and the adders stay fixed while produced parts rise, so each part carries a smaller share. A larger batch genuinely lowers the cost per produced part.

Last reviewed 2026-10-01.