Compound Interest Calculator
See how savings grow with compounding over time.
Balance after 20 years
$300,850.72
- Total contributed
- $130,000.00
- Interest earned
- $170,850.72
- Growth multiple
- 2.31 ×
How this is calculated
A = P(1+r/n)ⁿᵗ + PMT·((1+r/n)ⁿᵗ − 1)/(r/n)
r/n = 7% / 12 = 0.00583333 per period
240 periods over 20 years
Final balance 300850.72 = 130000 contributed + 170850.72 interest
Computed on your device — nothing is sent anywhere.
How it works
See how savings grow with compounding over time. Runs 100% in your browser, so your files never leave your device. Free, fast, no signup.
Questions about compound interest calculator
Yes — no watermark, no daily cap, no signup. Pro raises the file-size and batch limits, but the tool itself is not gated.
No. This tool runs entirely in your browser. Open your network inspector and watch while it works — there are no file uploads, because there is no upload endpoint.
Up to 10 files at 15 MB each. Everything runs in your browser, so the real ceiling is your device’s memory — the cap keeps a large file from exhausting the tab.