Calculate half-life from decay rates for radioactive isotopes, medications, and substances. Free tool with instant results, formulas, and examples for physics, medicine, and archaeology.
Calculate half-life from decay rate for radioactive isotopes, medications, or any exponentially decaying substance. Half-life is the time it takes for a quantity to reduce to half its initial value.
The half-life is calculated using the following formula:
Where λ (lambda) is the decay constant, which represents the rate at which the substance decays.
What this means:
After 0.00 time units, the quantity will decrease from 100 to {{halfQuantity}} (half the initial value).
The graph shows how the quantity decreases over time. The vertical red line indicates the half-life point, where the quantity has decreased to half of its initial value.
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