Two sides of the same question
The pension calculator works in two modes.
- Duration - you have the capital and want to know how long it lasts at a given monthly withdrawal.
- Capital needed - you know how much you want to withdraw and for how long, and want to know what you need to save up.
Both run the same way: each month the capital first earns its return, then the withdrawal comes out of it.
What each field means
- Initial capital - what you have when withdrawals start.
- Monthly withdrawal - what you take home per month, after tax.
- Return on capital - what the capital earns while you draw on it. A pension portfolio is usually more conservative, so 4-8 % is the usual reference rather than 10 %.
- Annual inflation - drives the real value of the withdrawals, and with indexation on, the size of the withdrawals themselves.
- Index withdrawals to inflation - the switch that matters most. With it on, the withdrawal grows every year by inflation so that it keeps its purchasing power.
An example
500 000 ₴ of capital, 5 000 ₴ withdrawn monthly, 8 % return, 10 % inflation (consumer price inflation per the NBU, October 2026), indexation on:
- it lasts 8 years 3 months
- total withdrawn: 713 151 ₴
- what those withdrawals are worth in today's money: 468 435 ₴
Now switch indexation off and the same capital lasts 13 years 10 months, five and a half years longer. The return did not change - what changed is that in the first case you end up withdrawing 10 718 ₴ a month by the end rather than 5 000 ₴.
The withdrawal schedule
The table under the calculator shows each year on its own: what was withdrawn, what the capital earned over the same year, and what is left at the end of it. You can see the point where the growth stops covering the withdrawals and the capital starts shrinking - usually well before it hits zero.
The last row is often partial: if the capital runs out mid-year, the month count sits next to the year number.
Withdrawal rate
The calculator shows what share of the capital you withdraw in the first year and colours it. Up to 4 % is the classic safe reference for long horizons; 4-8 % takes discipline and a willingness to cut spending; over 8 % drains the capital fast.
An example in the second mode
To withdraw the same 5 000 ₴ a month for 20 years, indexed to 10 % inflation at an 8 % return, you need 1 338 292 ₴ to start with. Over those 20 years you withdraw 3 436 500 ₴, and the final withdrawal is 30 580 ₴ a month.
What the calculator leaves out
It assumes a steady return and steady inflation. In reality the sequence of returns matters a lot: a few bad years right at the start of withdrawals hurt far more than the same years at the end. State pension, tax on income and one-off large expenses are not included either.