Calculate DPU
Enter inspection data to measure process quality and defect pressure.
Example Data Table
Use this sample to compare lots and spot which batches need quality attention.
| Lot | Units Inspected | Total Defects | Opportunities per Unit | DPU | First Pass Yield | DPMO |
|---|---|---|---|---|---|---|
| A-101 | 1,200 | 24 | 5 | 0.0200 | 98.02% | 4,000 |
| B-204 | 980 | 31 | 4 | 0.0316 | 96.89% | 7,908 |
| C-118 | 1,500 | 18 | 6 | 0.0120 | 98.81% | 2,000 |
| D-322 | 860 | 22 | 5 | 0.0256 | 97.47% | 5,116 |
| E-417 | 1,320 | 29 | 4 | 0.0220 | 97.83% | 5,492 |
Formula Used
DPU measures how many defects exist on average for each inspected unit. Lower values indicate a healthier process.
How to Use This Calculator
- Enter the number of inspected units from your batch, line, or audit sample.
- Add the total defects found. Count each defect event, not only defective units.
- Optionally enter opportunities per unit if you also want DPO and DPMO.
- Add cost per defect and inspection hours if you want operational insight.
- Set a target DPU to compare actual performance against expected limits.
- Click Calculate DPU to show results, chart, CSV export, and PDF export.
Frequently Asked Questions
1. What does DPU mean in quality control?
DPU means defects per unit. It shows the average number of defects found on each inspected unit. Lower DPU values indicate fewer defects and a more stable process.
2. How is DPU different from DPO?
DPU divides defects by units inspected. DPO divides defects by total defect opportunities. DPO is more detailed when each unit can fail in several possible ways.
3. Why is first pass yield included?
First pass yield estimates how many units pass without requiring rework. It helps managers connect defect counts to process efficiency and customer-facing quality performance.
4. Should repeated defects on one unit be counted?
Yes. DPU tracks total defect events. If one unit has multiple separate defects, each defect should be counted because each one adds repair effort and process risk.
5. What is a good DPU value?
A good DPU depends on your product, industry, tolerance limits, and customer requirements. In general, lower is better, and trends matter as much as single batch results.
6. Can this calculator help with Six Sigma work?
Yes. When you enter opportunities per unit, it also calculates DPO and DPMO. Those measures are commonly used in Six Sigma process capability reviews.
7. What happens when defects are zero?
If defects are zero, DPU becomes zero, defects per 100 units becomes zero, and the estimated first pass yield becomes very close to 100 percent.
8. Why export the results to CSV or PDF?
Exports help with audits, shift reviews, supplier meetings, and management reporting. CSV works well for spreadsheet analysis, while PDF is useful for clean sharing and recordkeeping.