Calculate how far an experimental value sits from a true or accepted value, as a percent.
| Error (%) | – |
Use this calculator in a lab or homework check: you measured one number and you know the accepted or theoretical value. Percent error is always non-negative; it does not tell you the direction of the miss.
The calculation is: percent error = |experimental − true| / |true| × 100. The true value cannot be 0. This is not percentage change (which keeps a sign and uses the start as the baseline) and not percent difference (which divides by the average of both numbers).
Experimental: The value you measured.
True value: The accepted, theoretical, or reference value. Cannot be 0.
Error (%): Absolute percent error relative to the true value.
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