For education and planning only. This app is not financial advice, tax advice, or investment advice. Results are estimates based on the numbers you enter.
What the app does
Project compound growth with periodic contributions, or model withdrawals over time. Adjust inputs and the chart updates instantly — no Calculate button.
Growth mode
- Enter starting balance, annual return, years, and periodic additions.
- Choose compounding frequency and contribution frequency (Daily through Yearly).
- See future value, total contributed, interest earned, a chart, and an optional year-by-year table.
Withdrawal mode
- Enter starting balance, return, years, and periodic withdrawal amount.
- The main result shows ending balance after your chosen period.
- Negative balances appear in red when withdrawals exceed growth.
How numbers are calculated
- End of period: contributions and withdrawals are applied at the end of each cash-flow period (no beginning/end toggle).
- Annual return: treated as a nominal APR, divided by the compounding frequency (APR ÷ n), then applied each compound period.
- Different frequencies: if compounding and contribution/withdrawal frequencies differ, the app simulates on the finer time step.
- Withdrawal floor: balance never goes below zero. When the account is empty, further withdrawals and compounding stop for that run.
- Chart and year table: yearly snapshots of a more detailed simulation. The table’s Added / Withdrawn and Interest columns are that year’s totals.
Currency symbol
Tap the code next to Starting balance to change how amounts are formatted (USD, EUR, GBP, JPY, and other major symbols). This is not currency conversion — the app does not fetch exchange rates. A balance of 10,000 shown with € still means the number 10,000 you typed, not euros converted from dollars.
Contributions and withdrawals
Contribution amount (Growth) or Withdrawal amount (Withdrawal) is how much you add or take out each time. How often below sets whether that is monthly, weekly, and so on — the same pattern as other compound calculators. Tap the i next to Compounding or How often in the app for a short reminder.
Slide your finger across the chart to inspect a point in time. Elapsed time and balance appear above the chart.
Saved scenarios
Tap Save current to store up to eight scenarios on your device. Open the clock icon at the top to restore a saved set.
Send feedback
Use Settings → Send feedback for a one-way in-app message. We read feedback when we can and cannot reply inside the app. Do not include account numbers or other sensitive personal data.