Finance & investing · NUMORA

How Long Money Lasts Calculator

You have a pot you can spend. How far does today's pace last — or, to last until a given age, what's the most you can take?

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How to use

Three questions on one ledger: how long, max spend to last N years, and remaining balance. Frequency, nominal vs APY, inflation.

Formula

Level monthly draw: n = ln(W / (W − P r)) / ln(1+r). Inflation and other modes use monthly simulation; max spend is binary-searched.

FAQ

Is this How Long Money Lasts calculator accurate?

The formula and assumptions are shown on the page, and the engine is covered by audit tests. Results are for reference — not financial or medical advice.

Do I need an account?

No. Calculations run in your browser. Recents can stay on this device.

What inputs do I need?

Three questions on one ledger: how long, max spend to last N years, and remaining balance. Frequency, nominal vs APY, inflation.

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