Business Tools
Compound Interest Calculator
Watch savings compound with contributions, year by year.
✓ Free
✓ No account
◉ Runs on this device
Business Tools
Powering up the tool…
TOOL COMPOUND-INT
What this tool does
About the compound interest calculator
Principal, monthly contributions, any compounding frequency — final balance, growth split and the annual ledger.
How to use it
- Enter starting amount and monthly contribution.
- Set the annual rate and years.
- Pick compounding frequency.
- Read final balance, total paid in, and growth — with the yearly ledger.
Useful for
- Project a savings pot over a decade.
- See what starting five years earlier is worth.
- Compare monthly compounding against yearly.
Straight answers
Compound Interest Calculator FAQ
Why does starting early matter so much?
Because growth compounds on growth: year ten’s interest is earned partly on year one’s interest. The yearly ledger makes it visible — the last years add more than the first, which is the whole argument for starting now.
Is this what my bank will actually pay?
It is the mathematics at a constant rate — real accounts change rates, charge fees and attract tax. Planning arithmetic, honestly labelled; not advice, not a promise.