Compound Interest Calculator
Project growth with compound interest.
Interest earning interest
Compound interest grows on both principal and prior interest, following A = P(1 + r/n)^(nt). $10,000 at 7% compounded yearly becomes about $19,700 in ten years — the effect that makes early investing powerful.
Compounding frequency matters too — monthly compounding beats annual at the same rate — and contributing regularly rather than a lump sum changes the curve dramatically over decades.
A projection, not a promise
Real returns vary and are rarely constant, so treat this as illustrative. Your figures stay in the browser and are never uploaded.
Frequently Asked Questions
How does this compound interest calculator work?
It uses the numbers you enter and applies the visible formula or planning rule in your browser.
Is this financial advice?
No. This is an educational estimate for planning. Check important decisions with a qualified financial professional.
Are my numbers uploaded?
No. The calculation runs locally in your browser and nothing is stored by this page.
Need clearer pricing, financial models, or planning tools? Let us help.