Exponential Growth and Decay Calculator: Step-by-Step Solutions

Rate constant from data, doubling time or half-life, predictions. Every step of the solution is shown, as you would write it on paper, using exact fractions.

What it solves

A quantity changes at a rate proportional to itself: $dx/dt=kx$. Give the initial amount $x_0$ and one later measurement $x(t_1)=x_1$.

How to use it

1. Enter your own numbers or functions in the boxes (an example is already filled in, or press Random example).
2. Check the equation preview, then press Solve step by step.
3. Reveal the solution one step at a time with Next step, or show everything at once.

Need the theory first? Read Section 3.3: Rate Problems, which explains the method in small steps with worked examples and exercises, then come back and test yourself with the Chapter 3 quiz.

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