Percent Error Calculator
Compare an experimental value with the true value
Use this when you need a fast, accurate result — no sign-up, works entirely in your browser.
Percent error—
Absolute difference—
How to Use
- Enter your details into the fields above.
- Click the calculate button to get your result instantly.
- Use the clear button to start a new calculation.
Example
- Measured value 9.8, accepted value 10 → Percent error = 2% (absolute difference 0.2)
- Measured 52, accepted 50 → Percent error = 4% (difference 2)
Formula
Percent error = |measured − accepted| ÷ |accepted| × 100%. A result under 5% is usually considered accurate in lab work.
About Percent Error Calculator
Compare an experimental value with the true value. This free online tool gives you fast, accurate results without registration or downloads.
Everything runs locally in your browser, so your data is never uploaded or stored — privacy first.
Frequently Asked Questions
Is this tool free to use? +
Yes, it is completely free with no registration or download required.
Is my data private? +
Yes. Everything is processed locally in your browser. Nothing is uploaded or stored on our servers.
Does it work on mobile? +
Yes, it works on any device — phone, tablet, or desktop.