Free interactive chemistry · SIM-MEAS-001
Measurement and precision
Repeated readings land on a target: the centre is the true value. You see the difference between accuracy and precision.
Open the interactive simulation →How to use this simulation
- Choose a measuring instrument.
- Move the “Systematic error (bias)” slider to shift every reading the same way.
- Move the “Random error (spread)” slider to scatter the readings.
- Change the number of readings and watch the mean (red dot) and the statistics.
- Press “Measure again” for a fresh set.
What to notice
- Accuracy = the average is close to the true value. Bias spoils it and more readings do not fix it.
- Precision = readings are close to each other. Random error spoils it; averaging many readings helps.
Try this
Make the readings “precise but inaccurate”. Which slider did you need?
Try it for free →