Coming soon

Rule of 72 Calculator

Quickly estimate how long money takes to double.

What it will do

Instantly estimate how many years it takes an investment to double at a given rate of return, using the classic shortcut formula.

Why it matters

A fast mental-math tool for sanity-checking bigger projections without running a full calculator.

Status: Planned

We build calculators one at a time and don't promise exact dates — but we do read every request.

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