Future value Target amount Target date

Compound Interest Calculator

Plan savings goals in three modes — future value, target amount, and target date — all running locally in your browser.

Modes 3 planners Switch instantly with tabs
Frequencies Yearly → Daily Fine-tune compounding & contributions
Exports CSV Take the 12-row schedule with you

No sign-up. Works offline after the first load.

Savings planner

Select a mode to calculate growth, required contributions, or time to reach your goal.

Future value
Total contributed
Total interest
Required contribution
Total contributed
Total interest
Estimated time
Total contributed
Total interest

Turn projections into action

Experiment with contributions

  • Increase recurring contributions until the timeline fits your goal date.
  • Try lump-sum deposits by adding them as one-time contributions in the schedule export.
  • Run monthly, biweekly, and weekly contributions to match paycheck cadence.

Understand the growth

  • Compare total interest between modes to see how timing affects results.
  • Remember that all numbers are estimates — re-run as APRs change.
  • Use the schedule to track progress in your budgeting or portfolio tracker.

FAQ

Compound vs simple interest

Compound interest adds interest on interest each period, while simple interest only applies to principal. This planner models compound interest.

Contribution timing (end vs beginning)

Beginning-of-period contributions grow one extra interval. Switch between options to see the difference.

APR vs APY

APR is the nominal annual rate. APY folds in compounding. Choose the compounding frequency that matches your account to approximate APY.

Can I include withdrawals?

Yes. Enter contributions as negative numbers to model withdrawals or planned spending.