What is the Half-Life Calculator?
Half-life is the time it takes for half of a substance to decay or be removed. After one half-life 50% remains, after two 25%, after three 12.5%, and so on. Use it for radioactive isotopes (carbon-14 dating), medicines in the body or any exponential decay. Solve for any one unknown.
How to use the Half-Life Calculator
- Choose what to solve for.
- Enter the other three values (same time unit throughout).
- See the answer and the decay table.
Formula
N = N₀ × (½)^(t ÷ T½) · t = T½ × log₂(N₀ ÷ N) · Carbon-14 half-life ≈ 5,730 years.
This Half-Life Calculator is 100% free, needs no signup and runs privately in your browser – on phone, tablet or computer.
Last updated: · By NodifyTech