Exponential Decay Calculator
A = A₀ · e^(-kt). Compute remaining quantity, half-life, or decay constant.
Result
General calculation reads
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How to use this calculator
- Enter the initial amount, decay constant k, and elapsed time t.
- Read the remaining amount and half-life.
About this calculator
Exponential decay: A = A₀e^(-kt), with k > 0. Models radioactive decay, drug clearance, capacitor discharge, and any process where the decay rate is proportional to the remaining amount. Half-life — time for half to decay — equals ln(2)/k regardless of starting amount.
Frequently asked
How is k related to half-life?+
Why is half-life independent of starting amount?+
What's a real-world example?+
Is decay always exponential?+
Can the calculator handle drug clearance?+
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