# Defects Per Unit Calculator

> Work out defects per unit from your own defect and unit counts.

Page: https://freecalculator.tech/tools/defects-per-unit-calculator
Last reviewed: 2026-09-16

## Formula

DPU = Defects ÷ Units inspected

- DPU = Defects ÷ Units inspected.
- Inputs used: Defects found, Units inspected.
- Edge handling: Defects found is required.; Defects found cannot be negative.; Defects found must be no more than 1000000000000.; Units inspected is required.; Units inspected cannot be negative..

## Inputs

- Defects found
- Units inspected

## Worked example: 37 defects across 500 units

Counts defects, not defective units, so the figure can be above one.
1. Start with Defects found: 37, Units inspected: 500.
2. Apply the method: DPU = Defects ÷ Units inspected.
3. Counts defects, not defective units, so the figure can be above one.

## Common questions

### Where does this formula come from?

ASQ quality resources, defect measures: defects per unit counts defects rather than defective units. See the source link on this page.

### What kind of calculation is this?

Total defects counted divided by the number of units inspected. Check the formula, example, and limitations on this page before using the result for a real professional & industry decision.

### What are its limits?

Defects per unit is not a defective rate — a unit with three defects counts three times. Arithmetic over the counts entered — it cannot tell whether the inspection behind them was complete or consistent.

### How do I use the Defects Per Unit Calculator?

Enter the required values for Defects found, Units inspected. The calculator applies the formula on this page and shows the main result with any supporting breakdown so you can check the arithmetic.

### What formula does the Defects Per Unit Calculator use?

DPU = Defects ÷ Units inspected The visible formula section above lists the calculation path and the edge cases the page handles, so the result can be checked without relying on the form alone. Check the formula, example, and limitations on this page before using the result for a real professional & industry decision.

### Can the Defects Per Unit Calculator be used for exact decisions?

Use it as a calculation aid, not as a substitute for checking the underlying rule, contract, policy, or professional advice that applies to your situation. When a result depends on local rules, personal details, prices, or dates, enter those values yourself and confirm them before acting.

## Limitations and assumptions

- Inputs outside the supported range are rejected rather than forced into a result.
- The result depends on the values you enter for this defects per unit calculator; it does not supply missing rates, rules, prices, dates, or assumptions for you.

## Sources

- American Society for Quality — https://asq.org/quality-resources/process-capability

## Cite this page

- APA: Free Calculator. (2026, September 16). Defects Per Unit Calculator. https://freecalculator.tech/tools/defects-per-unit-calculator
- MLA: "Defects Per Unit Calculator." Free Calculator, 16 Sept. 2026, https://freecalculator.tech/tools/defects-per-unit-calculator.
- Link: Defects Per Unit Calculator — Free Calculator, https://freecalculator.tech/tools/defects-per-unit-calculator