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Half-life decay calculator
For a process described by a constant half-life, the remaining quantity declines exponentially with time.
Formula
Remaining amount = initial amount × (1/2)^(elapsed time ÷ half-life).
This mathematical model is useful in many educational contexts, including radioactive decay and idealized first-order processes. Real pharmacokinetic or biological systems may require more complex models.
Questions
Frequently asked questions
Does this calculator predict an individual drug level?
No. It is a mathematical half-life calculator and is not a substitute for individualized pharmacokinetic or medical assessment.