401(k) Calculator

How a 401(k) grows

Each paycheck you put a percentage of your salary into the plan, before income tax (traditional 401(k)). Many employers add a match – for example 50% of what you contribute, up to 6% of your salary. The money is invested, and the growth compounds untaxed until you withdraw it in retirement.

Worked example

Age 35, salary $75,000 rising 3% a year, $30,000 already saved. You contribute 6% and your employer matches 50% up to 6% (another 3% of salary). At a 7% return, by 67 you have about $1,393,800: $236,300 from you, $118,100 from your employer and over $1 million of growth. In today’s money (2.5% inflation) that is about $632,000 – roughly $4,600 a month with the 4% rule.

Never leave the match on the table

The employer match is an instant 50–100% return. If you contribute less than the match cap, the calculator shows how much free money you are giving up. In the example, contributing 3% instead of 6% would cost $1,125 of match this year – and about $557,000 less at retirement.

2026 contribution limits

• $24,500 employee contributions (up from $23,500 in 2025).
• +$8,000 catch-up from age 50 – $32,500 in total.
• +$11,250 instead at ages 60–63 (SECURE 2.0) – $35,750 in total.
• Employer and employee contributions together are capped at $72,000.

The calculator caps your contribution at the limit for your age in every year.

Traditional or Roth 401(k)?

Traditional contributions lower your taxable income now and are taxed when you withdraw; Roth 401(k) contributions are taxed now and come out tax-free. The IRA calculator in this family compares the two for your tax rates.

Frequently asked questions