Science & Engineering

Relative & Percent Error

Compares a measured value with the true value and returns the relative and percent error. You can choose unsigned magnitude or keep the sign to see whether you over- or under-estimated.

How to use
  1. Enter the measured value and the true value.
  2. Choose unsigned magnitude or signed direction.
Try
Percent error
0.667%

Very good (1–5%) · measured is higher than true

Absolute error
0.3
Relative error
0.006667
Difference
0.3
For study and estimation. Verify against authoritative data before relying on a result.
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Common questions

What is the difference between relative and percent error?

Relative error is the absolute error divided by the true value, and percent error is just that figure multiplied by 100.

When is signed error useful?

Signed error tells you the direction of the mistake, so a negative result means your measurement came in below the true value.

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