Everyday utility

Half-Life Calculator

Calculate the remaining quantity of a substance after a given number of half-lives have elapsed. Use this Data and utilities tool to enter your numbers, review the result, and understand the key assumptions before making the next decision.

What you get
A focused calculator, clear explanation, common questions, and useful next tools.
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Result
Explanation
Common questions
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How this calculator works
The result depends on the numbers you enter and the assumptions shown below.

Half-life is the time for a quantity to reduce by half. Formula: N(t) = N₀ × (1/2)^(t/t½). Used in nuclear physics, pharmacology (drug half-life), and carbon dating.

Review the inputs carefully and treat the output as an estimate. For decisions involving money, taxes, health, law, or security, compare the result with trusted professional guidance when needed.

Frequently asked questions

What is a half-life?

Half-life (t½) is the time required for a quantity to fall to half its initial value. After n half-lives, the remaining amount is N₀ × (0.5)^n.