How the calculator works
- Your contributions: a share of your pay goes in each month, up to the yearly limit for your age.
- Your employer’s match: for example, 50% of what you put in, on up to 6% of your pay.
- Growth: your balance grows at the rate you choose, and your pay rises each year.
The result shows your balance at retirement, the same amount in today’s money (after inflation), and how much came from you, your employer and investment growth.
2026 limits
| 2026 limit | |
|---|---|
| Your contributions | $24,500 |
| Catch-up from age 50 | $8,000 |
| Catch-up at ages 60 to 63 | $11,250 (instead of $8,000) |
| You and your employer together | $72,000, plus catch-up |
From 2026, if you earned over $150,000 from your employer in the previous year, your catch-up contributions have to go in as Roth. The 2027 limits are due from the IRS soon: see our key dates.
How much difference does saving more make?
Starting at 30 on $75,000 with $25,000 saved, a 50% match on up to 6% of pay, 6% growth a year and 3% pay rises:
| You put in | At 67 | In today's money |
|---|---|---|
| 3% of pay | $869,000 | $348,000 |
| 6% of pay | $1,522,000 | $610,000 |
| 10% of pay | $2,102,000 | $843,000 |
| 15% of pay | $2,828,000 | $1,134,000 |
At 3%, you only get half the match: $1,125 of free money missed in the first year alone.
Starting earlier matters even more. Putting in 10% from nothing, retiring at 67:
| Starting at | At 67 | You put in | Growth |
|---|---|---|---|
| 25 | $2,703,000 | $615,000 | $1,903,000 |
| 35 | $1,295,000 | $394,000 | $783,000 |
| 45 | $563,000 | $229,000 | $266,000 |
Most of a long-run balance is growth, not what you put in, which is why the first years count the most.
Get the full match first
An employer match is part of your pay that you only get by saving. With a 50% match on up to 6% of pay, putting in 6% gets you an extra 3% of your salary every year. Putting in less leaves that money on the table, so reach at least the full match before paying extra on low-interest debt or saving elsewhere.
Traditional or Roth 401(k)?
- Traditional contributions lower your tax now, and you pay tax when you take the money out in retirement.
- Roth contributions get no tax break now, but everything you take out in retirement, growth included, is tax-free.
If your tax rate now is higher than it will be in retirement, traditional usually wins. If it’s lower, choose Roth. Many people split their contributions between the two. See Roth vs traditional.
Taking money out
Withdrawals before 59½ usually cost a 10% penalty on top of income tax, so a 401(k) is best left alone until retirement. When you leave a job, you can usually leave your 401(k) where it is, or move it to your new employer’s plan or an IRA with a direct rollover, which keeps it invested without tax. In retirement, see how long your savings could last with the retirement withdrawal calculator, and from 73 the RMD calculator works out what you must take each year.
How much should you save?
Many people aim for 15% of their pay in total, including the match, and raise it by 1% a year until they get there. Starting later means saving more each year to catch up. See how much to save for retirement, and compare with Social Security in the Social Security calculator.