Savings Goal Calculator
Know what you want to save, how long you have, or how much you can set aside each month? Enter any two and this calculator works out the third. You can also add a starting balance and an annual interest rate (use 0% for a plain savings account with no interest). A year-by-year table shows how much is your own deposits and how much is interest. For a deeper look at investment growth, try the Investment Growth Simulator.
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Choose what to calculate
Notes
- Results are estimates only. Taxes on interest (deposit interest in Japan is normally subject to 20.315% withholding tax) and fees are not included, so your after-tax amount will be lower.
- Deposits are made at the end of each month, and interest compounds monthly at the annual rate divided by 12. Actual banks may calculate interest differently (daily accrual, semiannual crediting, and so on).
- When solving for time, the result is the first whole month in which the balance reaches your target. The monthly amount and the interest rate are assumed to stay constant throughout.
- Everything you enter is processed in your browser and never sent to a server.
FAQ
Does it work with no interest (0% annual rate)?
Yes. At 0%, the final balance is simply your starting balance plus monthly savings times the number of months, and the monthly amount needed is (target minus starting balance) divided by the number of months.
Why is the result slightly above my target when solving for time?
The time is the first whole month in which the balance reaches your target, so the balance at that point equals or slightly exceeds it. The year-by-year table shows the balance in the final month.
Are taxes on the interest included?
No. Deposit interest in Japan is normally taxed at 20.315%, so the amount you actually receive is a bit lower than shown. With low-rate accounts the difference is small, but treat the result as a rough guide.
Are deposits made at the start or end of the month?
At the end of each month. A deposit does not earn interest in the month it is made. If you deposit at the start of the month, this calculator slightly underestimates the result.
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