Error, Quantified

Percent error turns "close enough" into a number you can grade against. This percent error calculator computes both the magnitude of the deviation and its direction, so a lab report can say exactly how far a measurement landed from the accepted value.

Signed Error Finds Bias

If every measurement comes out low, random error is not the culprit — something is systematically off, like a mis-calibrated scale or a timing method that starts late. The signed percent error makes that pattern visible instead of burying it in absolute values.

Putting It in Context

There is no universal threshold: a 2% error is a great pendulum experiment and a terrible analytical chemistry result. Report the percent error alongside the method's expected precision, and use the verdict readout here as a first-pass sanity check.