Percent Error Calculator
Measure how far an observed value is from the true value as a percentage, common in science and quality checks. Enter observed value and true value…
8 of 8 free uses remaining today
Measure how far an observed value is from the true value as a percentage, common in science and quality checks. Enter observed value and true value to see percent error when you calculate.
Worked example
Example calculated from the starting values. Enter your own values and press Calculate to get your result.
With the default inputs (observed value = 98, true value = 100), the results are: percent error 2.000 %.
Quick reference: observed value vs result
Reference table based on the example values; it is not your calculation result.
| Observed value | Percent error |
|---|---|
| 49 | 51.000 % |
| 98 | 2.000 % |
| 196 | 96.000 % |
| 490 | 390.000 % |
| 980 | 880.000 % |
| 1,960 | 1,860.000 % |
Frequently asked questions
What formula does this calculator use?
Percent error = abs(obs-tr) ÷ abs(tr) × 100. Variables: obs = observed value, tr = true value.
What do I need to enter?
You need observed value, true value. Results update as you type.
What is an example result?
With the default inputs (observed value = 98, true value = 100), the results are: percent error 2.000 %.
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