How to Calculate Percent Error
What is Percent Error?
Percent error measures how far an experimental measurement is from the accepted (true) value, expressed as a percentage. Used in science labs to assess measurement accuracy.
Formula
Step-by-Step Guide
- 1% error = |Experimental − Theoretical| / Theoretical × 100
- 2Sign indicates over or under-measurement
- 3Lower % error = better experimental technique
- 4Systematic errors affect accuracy; random errors affect precision
Worked Examples
Frequently Asked Questions
What is Percent Error?
Percent error measures how far an experimental measurement is from the accepted (true) value, expressed as a percentage. Used in science labs to assess measurement accuracy
How accurate is the Percent Error calculator?
The calculator uses the standard published formula for percent error. Results are accurate to the precision of the inputs you provide. For financial, medical, or legal decisions, always verify with a qualified professional.
What units does the Percent Error calculator use?
This calculator works with inches, percentages. You can enter values in the units shown — the calculator handles all conversions internally.
What formula does the Percent Error calculator use?
The core formula is: % error = |Experimental − Theoretical| / Theoretical × 100. Each step in the calculation is shown so you can verify the result manually.
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