Free calculators · No sign-up · Every formula shown
The exact math behind your money.
Put in your own numbers and find out what your savings grow to, what you'd need to retire on, and what fees are costing you. Free, no sign-up. Every tool shows the formula it used and names every assumption, so you can check the work rather than trust it.
Worked example — compound interest
$10,000 at 7%, compounded monthly, plus $500/month for 30 years
A = P(1+r/n)nt + PMT·[((1+r/n)nt−1)/(r/n)]
- Total deposits
- $190,000.00
- Interest earned
- $501,150.47
- Future value
- $691,150.47
The formula, on the page. Every tool shows its math and a worked example.
Every assumption named. Rates, timing, and scope limits are labeled, never buried.
Stateless and free. No sign-up, no stored data. Informational, not financial advice.
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