Free · Math · Science

Half-Life Calculator

Calculate the remaining amount, elapsed half-lives, and decay constant for exponential decay.

  • Checked formula
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Calculator inputs

Enter your values

Result

Your calculation

Remaining amount
12.5
Amount decayed
87.5
Half-lives elapsed
3
Decay constant
0.0866434
per time unit

How to use this calculator

  1. Enter the known values using the units shown.
  2. Choose the calculation you want when more than one method is available.
  3. Calculate, then review the result and the worked formula together.

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