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RetireEarlyGuide

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Calculators

Free, easy-to-use financial calculators for financial independence and everyday maths — compound interest, investment growth, your FIRE number, savings rate, percentages and more.

FIRE & Investing

Compound Interest Calculator

See how an initial amount plus regular contributions can grow over time with compound interest.

Investment Return Calculator

Find out what a one-off investment could be worth in the future — 'if I invest X at Y% for Z years'.

FIRE Number Calculator

Estimate the portfolio you need to retire early and how many years it may take to get there.

Savings Rate Calculator

Calculate your savings rate and see roughly how many years of work it could buy back.

Rule of 72 Calculator

Estimate how long it takes your money to double at a given rate of return — or the rate needed.

Everyday

Percentage Calculator

Work out percentages three ways: X% of Y, X is what % of Y, and percentage increase or decrease.

Age Calculator

Calculate an exact age in years, months and days from a date of birth — plus totals in weeks and days.

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