How the 401(k) calculator works
Enter your age, salary, contribution rate and your employer's matching formula. Each year the calculator adds your contributions and the employer match, grows the balance at your expected rate of return and raises your salary. Contributions are capped at the IRS limits — the 2026 employee deferral limit is $24,500 — and catch-up contributions are added from age 50 if your contribution percentage allows it.
2026 401(k) contribution limits
| Limit | Amount |
|---|---|
| Employee elective deferrals | $24,500 |
| Catch-up contribution, age 50+ | $8,000 |
| "Super catch-up", ages 60–63 | $11,250 |
| Total employee + employer contributions | $72,000 |
| IRA contribution limit (separate) | $7,500 |
Starting in 2026, workers whose prior-year wages from the employer exceeded about $150,000 must make catch-up contributions as Roth (after-tax) contributions under the SECURE 2.0 Act.
Always capture the full employer match
An employer match is an instant, guaranteed return on your money. With a common "50% of the first 6%" match, contributing 6% of a $70,000 salary ($4,200) earns an extra $2,100 a year — a 50% return before any investment growth. If you contribute less than the match threshold, you leave free money on the table. Try lowering your contribution in the calculator to see the long-term cost.
Traditional vs. Roth 401(k)
Traditional contributions reduce your taxable income today, and withdrawals in retirement are taxed. Roth contributions are made after tax, but qualified withdrawals — including all the growth — are tax-free. If you expect a higher tax rate in retirement, or you are early in your career, Roth can be attractive. Many people split contributions between both. See how pre-tax contributions change your paycheck with our paycheck calculator.
How much do I need to retire?
A popular rule of thumb is the 4% rule: withdrawing 4% of your portfolio in the first year of retirement (then adjusting for inflation) has historically lasted about 30 years. That means a $1 million balance supports roughly $40,000 a year. The calculator converts your result into an estimated monthly income in today's dollars so you can compare it with your current spending. Remember that Social Security will add to this income.
Assumptions
Returns are assumed constant each year; real markets go up and down. Results ignore fees, taxes on withdrawals, vesting schedules and loans or hardship withdrawals. Treat the result as a planning estimate.
Frequently asked questions
What is the 401(k) limit for 2026?
How much should I contribute to my 401(k)?
What happens if I contribute more than the limit?
Does the employer match count toward the $24,500 limit?
Sources & methodology
This calculator was last reviewed on November 1, 2026. Figures are based on the following official and primary sources:
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