$1,500 a month for 10 years at returns from 4% to 10%
| Return | Balance | Of which growth | In today’s dollars |
|---|---|---|---|
| 4% | $220,044 | $40,044 | $163,733 |
| 5% | $231,545 | $51,545 | $172,291 |
| 6% | $243,710 | $63,710 | $181,343 |
| 7% | $256,578 | $76,578 | $190,918 |
| 8% | $270,186 | $90,186 | $201,044 |
| 10% | $299,796 | $119,796 | $223,076 |
Year by year at 7%
| Year | Put in so far | Balance | In today’s dollars |
|---|---|---|---|
| 1 | $18,000 | $18,570 | $18,030 |
| 2 | $36,000 | $38,441 | $36,234 |
| 3 | $54,000 | $59,702 | $54,636 |
| 4 | $72,000 | $82,452 | $73,257 |
| 5 | $90,000 | $106,794 | $92,121 |
| 6 | $108,000 | $132,840 | $111,251 |
| 7 | $126,000 | $160,709 | $130,671 |
| 8 | $144,000 | $190,529 | $150,405 |
| 9 | $162,000 | $222,437 | $170,479 |
| 10 | $180,000 | $256,578 | $190,918 |
The range in 1,000 simulated markets
A 7% average does not arrive as 7% every year. In 1,000 simulated sequences of returns averaging 7% with 12% volatility, this is where $1,500 a month ended up: 1 in 10 markets finished below the first figure, half below the middle one, and 1 in 10 above the last.
| After | Weak (1 in 10 lower) | Middle | Strong (1 in 10 higher) |
|---|---|---|---|
| 5 years | $87,119 | $105,225 | $128,100 |
| 10 years | $189,055 | $248,266 | $328,192 |
The middle of the simulation sits below the steady 7% figure of $256,578 because ups and downs cost compounding: a 20% loss needs a 25% gain to get back.
What $256,578 would pay in retirement
At a 4% first-year withdrawal, $256,578 pays about $10,263 a year, $855 a month, before tax; in today’s dollars that is about $7,637 a year. How long a balance near it lasts at each withdrawal: how long $250,000 lasts. To stop saving early and let growth do the rest, see Coast FIRE numbers by age.
$18,000 a year is more than the 2026 IRA limit of $7,500 but fits in a 401(k), 403(b) or TSP, whose limit is $24,500. See contribution limits, the 401(k) calculator and the Roth IRA calculator.
$1,500 a month for other terms
| Years | Balance | In today’s dollars |
|---|---|---|
| $1,500 a month for 5 years | $106,794 | $92,121 |
| 10 years | $256,578 | $190,918 |
| $1,500 a month for 15 years | $466,657 | $299,529 |
| $1,500 a month for 20 years | $761,305 | $421,516 |
| $1,500 a month for 25 years | $1,174,563 | $560,978 |
| $1,500 a month for 30 years | $1,754,179 | $722,698 |
| $1,500 a month for 35 years | $2,567,120 | $912,312 |
| $1,500 a month for 40 years | $3,707,313 | $1,136,502 |
Other amounts for 10 years
$50 a month: $8,553, $100 a month: $17,105, $150 a month: $25,658, $200 a month: $34,210, $250 a month: $42,763, $300 a month: $51,316, $400 a month: $68,421, $500 a month: $85,526, $600 a month: $102,631, $750 a month: $128,289, $1,000 a month: $171,052, $2,000 a month: $342,103, $2,500 a month: $427,629, $3,000 a month: $513,155, $5,000 a month: $855,259.
How it is worked out
Monthly amounts are deposited at the end of each month and compounded monthly at the rate that equals the annual return; lump sums compound once a year. The headline return is 7% a year, the Trinity-style average the site’s retirement pages use; stock-heavy portfolios have averaged more over long periods and bond-heavy ones less, which is why every page shows 4% to 10%. Today’s dollars divide by 3% inflation a year. The range comes from 1,000 simulated sequences of yearly returns averaging 7% with 12% volatility, with each year’s deposits added through the year. Fees and taxes are not taken out. More on the methodology page.