What does “100% return” mean here?

A 100% cumulative return means your capital doubles: you end with 2× what you started with. This calculator shows how long that takes at a steady annual return with profits reinvested once per year.

How is doubling time calculated?

With annual compounding, years to double = ln(2) / ln(1 + r) where r is the annual rate as a decimal (e.g. 12% → 0.12). The Rule of 72 is a quick approximation: 72 divided by the rate in percent.

Time to 100% Return Calculator — How Long to Double Your Money? | Clearmind

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Set your expected return

Annual return (CAGR-style)12%

1%100%

Exact % (type your own)

Optional — starting amount (₹)

Doesn’t change the time — it only personalises the “₹X → ₹Y” copy below.

At 12% a year, ₹10.00 L grows to ₹20.00 L — a 100% return — in about 6.12 years.

Rule of 72 estimates ~6.00 years (72 ÷ 12). The exact formula gives 6.12 years — within ~2% of the shortcut, which is why the rule is so handy for mental math.

Exact formula vs Rule of 72

Same slider — two ways to estimate. Bar length scales to the larger value so you can see how close the shortcut lands.

Exact (ln 2 ÷ ln(1+r))6.12 yrs

Rule of 72 (72 ÷ rate)6.00 yrs

Gap: 0.12 yrs (~1.9% vs exact)

Doubling time by return rate

Tap a row to jump the slider — bar length is years to double (longer = more years of compounding needed).

6.1163

Exact years (ln 2 / ln(1+r))

6.00 yrs

Rule of 72 estimate

~1.9%

Shortcut vs exact

Assumes a constant annual return and annual compounding (end-of-year). Real markets are not smooth; taxes, fees, and volatility change outcomes. Illustrative only — not investment advice.