See how a deposit grows over time with compound interest and optional regular contributions.
How the interest calculator works
This interest calculator compounds a starting balance over time and adds any regular contributions, showing the future value and interest earned. It’s the same engine as the compound interest calculator, framed for savings and deposits.
Step by step
- Enter your figures in the fields provided.
- The result updates as you type.
- Review the breakdown below the main number.
The calculation
future value = principal × (1 + rate)^periods + contributions compounded
A worked example
The calculator opens with a starting principal of 10,000. On those figures the future value is $20,096.61. Underneath, Future value comes out at $20,096.61 and Total contributions at $10,000. Change any field and every figure updates as you type.
Questions people ask about this
Is this simple or compound interest?
It uses compound interest, where earnings are added back and themselves earn interest.
Can I add monthly deposits?
Yes — add a regular contribution and each one compounds for the time it’s invested.