$1,500 a month for 40 years at returns from 4% to 10%
| Return | Balance | Of which growth | In today’s dollars |
|---|---|---|---|
| 4% | $1,741,596 | $1,021,596 | $533,898 |
| 5% | $2,223,787 | $1,503,787 | $681,717 |
| 6% | $2,861,517 | $2,141,517 | $877,217 |
| 7% | $3,707,313 | $2,987,313 | $1,136,502 |
| 8% | $4,831,619 | $4,111,619 | $1,481,166 |
| 10% | $8,325,522 | $7,605,522 | $2,552,246 |
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 |
| 5 | $90,000 | $106,794 | $92,121 |
| 10 | $180,000 | $256,578 | $190,918 |
| 15 | $270,000 | $466,657 | $299,529 |
| 20 | $360,000 | $761,305 | $421,516 |
| 25 | $450,000 | $1,174,563 | $560,978 |
| 30 | $540,000 | $1,754,179 | $722,698 |
| 35 | $630,000 | $2,567,120 | $912,312 |
| 40 | $720,000 | $3,707,313 | $1,136,502 |
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) |
|---|---|---|---|
| 20 years | $459,547 | $711,058 | $1,129,154 |
| 40 years | $1,633,372 | $3,244,711 | $6,464,910 |
The middle of the simulation sits below the steady 7% figure of $3,707,313 because ups and downs cost compounding: a 20% loss needs a 25% gain to get back.
What $3,707,313 would pay in retirement
At a 4% first-year withdrawal, $3,707,313 pays about $148,293 a year, $12,358 a month, before tax; in today’s dollars that is about $45,460 a year. How long a balance near it lasts at each withdrawal: how long $4 million 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 |
| $1,500 a month for 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 |
| 40 years | $3,707,313 | $1,136,502 |
Other amounts for 40 years
$50 a month: $123,577, $100 a month: $247,154, $150 a month: $370,731, $200 a month: $494,308, $250 a month: $617,886, $300 a month: $741,463, $400 a month: $988,617, $500 a month: $1,235,771, $600 a month: $1,482,925, $750 a month: $1,853,657, $1,000 a month: $2,471,542, $2,000 a month: $4,943,084, $2,500 a month: $6,178,855, $3,000 a month: $7,414,626, $5,000 a month: $12,357,710.
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.