Half-Life Calculator

Estimate how much of a quantity remains after a specified number of half-lives.

Remaining quantity

12.5

3 half-lives elapsed

Initial quantity100

Decayed87.5

Remaining percentage12.5%

About the Half-Life Calculator

Estimate how much of a quantity remains after a specified number of half-lives.

It runs entirely in your browser — nothing you type is sent to a server — and the result updates as you edit the inputs. Estimates are for educational and informational purposes only; see ourdisclaimer.

Common searches

radioactive decay
decay
exponential

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