$750 a month for 10 years at returns from 4% to 10%
| Return | Balance | Of which growth | In today’s dollars |
|---|---|---|---|
| 4% | $110,022 | $20,022 | $81,867 |
| 5% | $115,772 | $25,772 | $86,146 |
| 6% | $121,855 | $31,855 | $90,672 |
| 7% | $128,289 | $38,289 | $95,459 |
| 8% | $135,093 | $45,093 | $100,522 |
| 10% | $149,898 | $59,898 | $111,538 |
Year by year at 7%
| Year | Put in so far | Balance | In today’s dollars |
|---|---|---|---|
| 1 | $9,000 | $9,285 | $9,015 |
| 2 | $18,000 | $19,220 | $18,117 |
| 3 | $27,000 | $29,851 | $27,318 |
| 4 | $36,000 | $41,226 | $36,629 |
| 5 | $45,000 | $53,397 | $46,061 |
| 6 | $54,000 | $66,420 | $55,626 |
| 7 | $63,000 | $80,355 | $65,336 |
| 8 | $72,000 | $95,265 | $75,203 |
| 9 | $81,000 | $111,218 | $85,240 |
| 10 | $90,000 | $128,289 | $95,459 |
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 $750 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 | $43,560 | $52,612 | $64,050 |
| 10 years | $94,527 | $124,133 | $164,096 |
The middle of the simulation sits below the steady 7% figure of $128,289 because ups and downs cost compounding: a 20% loss needs a 25% gain to get back.
What $128,289 would pay in retirement
At a 4% first-year withdrawal, $128,289 pays about $5,132 a year, $428 a month, before tax; in today’s dollars that is about $3,818 a year. How long a balance near it lasts at each withdrawal: how long $150,000 lasts. To stop saving early and let growth do the rest, see Coast FIRE numbers by age.
$9,000 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.
$750 a month for other terms
| Years | Balance | In today’s dollars |
|---|---|---|
| $750 a month for 5 years | $53,397 | $46,061 |
| 10 years | $128,289 | $95,459 |
| $750 a month for 15 years | $233,329 | $149,765 |
| $750 a month for 20 years | $380,652 | $210,758 |
| $750 a month for 25 years | $587,281 | $280,489 |
| $750 a month for 30 years | $877,089 | $361,349 |
| $750 a month for 35 years | $1,283,560 | $456,156 |
| $750 a month for 40 years | $1,853,657 | $568,251 |
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, $1,000 a month: $171,052, $1,500 a month: $256,578, $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.