Compound Interest Calculator

Watch savings grow — compounding, monthly contributions, and the year-by-year table.

Runs locally — nothing you enter leaves your device

Investment details

Starting amount

Annual rate %

Years

Monthly contribution

Compounding

Results

—Final balance

—Total contributed

—Total interest earned

Fixed-rate compounding math for orientation — real returns vary. Not financial advice.

Year-by-year

Year · Balance · Interest that year · Contributed to date

Contributions are added at month end, after that month's growth is applied.