Science & Environment
Radioactive Decay Half-Life Calculator
Calculate the remaining quantity of a radioactive substance after a given time using its half-life.
Your inputs
Change any value to update the result instantly.
Remaining amount
88.6062 g
Decayed amount
11.3938 g
Decay constant (λ)
0.0001 1/year
Fraction remaining
0.8861
Formula and working
N(t) = N0 × e^(-λt), λ = ln(2)/t½
- 1
Collect the inputs
Initial amount (N0) = 100 g; Half-life = 5,730 years; Elapsed time = 1,000 years
- 2
Apply the formula
N(t) = N0 × e^(-λt), λ = ln(2)/t½
- 3
Result
Remaining amount = 88.6062 g
Frequently asked questions
Important limitation
This is an educational estimate based only on the values and formula shown. Verify current rates, rules, units, and professional standards before relying on the result. It is not personalized financial or investment advice.
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