Half-Life (Radioactive Decay) Calculator
Calculate the remaining amount of substance based on the elapsed time.
g
years
years
Result
25 g
Remaining amount: 25 g (25%)
Result in all units
Step-by-step solution
remaining = initial × (1/2)^(t/T)
What Is Half-Life?
Half-life is the time it takes for half of a radioactive substance to decay. It is a constant value specific to each substance.
How is it calculated?
How Is It Calculated?
N = N₀ × (1 ÷ 2)^(t ÷ T)
T: half-life, t: elapsed time.
- Enter the initial amount, the elapsed time and the half-life.
Frequently Asked Questions
What remains after two half-lives?
One quarter of the initial amount remains (first half, then half of that).