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Compound Interest Calculator

See how your money grows over time. The earlier you start, the more powerful compounding becomes.

Calculate My Returns

The Power of Compounding: An Example

Invest $10,000 at 7% annual return:

$19,672
After 10 years
$38,697
After 20 years
$76,123
After 30 years
$149,745
After 40 years

Your $10,000 grows to nearly $150,000 - that's 15x your original investment!

Why Compound Interest Matters

Time Is Your Friend

The earlier you start, the more time your money has to compound. 10 years makes a huge difference.

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Exponential Growth

Your money doesn't grow linearly - it accelerates. The longer you wait, the faster it grows.

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Consistency Wins

Regular monthly contributions, even small ones, add up dramatically over decades.

Frequently Asked Questions

How does compound interest work?

Compound interest means you earn interest on your interest. $1,000 at 7% becomes $1,070 after year 1. Year 2, you earn 7% on $1,070, not $1,000. Over decades, this snowball effect is powerful.

What is the Rule of 72?

Divide 72 by your interest rate to estimate doubling time. At 7%: 72÷7 = ~10 years to double. At 10%: 72÷10 = ~7 years.

How much should I save monthly to become a millionaire?

At 7% return: save $400/month for 40 years, or $900/month for 30 years, or $2,000/month for 20 years. Starting early is key.

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