Half-Life Calculator

Half-life is the time it takes for a substance to reduce to half of its initial amount through decay. This concept is fundamental in fields like nuclear physics (for radioactive decay) and pharmacology (for drug clearance). Select which variable you want to solve for and enter the others.

Initial Quantity (N₀)

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Remaining Quantity (N(t))

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Time Elapsed (t)

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Half-Life Period (T)

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The Half-Life Formula

The calculation is based on the formula for exponential decay:

N(t) = N₀ * (1/2)^(t / T)

N(t) is the quantity remaining after time `t`.
N₀ is the initial quantity of the substance.
t is the time that has elapsed.
T is the half-life of the substance.