401(k) calculator
Project your 401(k) balance with your contributions, the employer match and IRS limits.
- Formula and assumptions shown
- Table and CSV export
- Runs in your browser
How it works
A 401(k) grows from three sources: what you contribute from each paycheck, what your employer adds as a match, and the investment return on the whole balance. The calculator adds all three year by year until the retirement age you enter.
Each year: salary = starting salary × (1 + raise)^(year − 1); your contribution = min(salary × contribution %, deferral limit + catch-up for your age); match = match % × min(your contribution, salary × matched-up-to %), limited so employee plus employer stay within the annual additions limit. The yearly total is deposited in 12 equal end-of-month amounts, and the balance compounds monthly at the annual return ÷ 12.
Your contribution is a share of salary, and salary can rise every year. The employer match is a percentage of your contributions, paid only on contributions up to a share of salary; with the defaults, the employer adds 50 cents per dollar on the first 6% of salary you contribute.
With limits applied, your own contributions stop at the 2026 IRS limit of $24,500, plus the catch-up of $8,000 from age 50 or $11,250 at ages 60 to 63, and employee plus employer contributions stay within the $72,000 annual additions limit.
Assumptions
- The 2026 IRS limits are held flat in every year; the IRS raises them for inflation, so later real limits are likely higher.
- Salary rises once a year; contributions and the match are deposited at the end of each month.
- The return is a constant nominal assumption, compounded monthly. Returns vary and are not guaranteed.
- No taxes, plan fees, vesting schedules, loans, hardship withdrawals or true-up contributions are modeled.
Worked example
Worked examples on this page use US dollars.
Age 35 to 65, $75,000 salary, 10% contribution, 50% match up to 6%
With a $25,000 starting balance, 3% yearly raises and a 7% return, the balance at 65 is $1,557,479.91: $356,815.62 of your contributions, $107,044.69 from the employer and $1,068,619.61 of growth. In year 1 you put in $7,500 and the employer adds $2,250. Contributing 6% instead of 10% gives $1,140,689.92, with the same employer match.
Step by step
- Work out the first year’s contribution. At 10% of a $75,000 salary you contribute $7,500, well under the 2026 limit of $24,500, so nothing is capped.
- Apply the employer match. The match is 50% of your contributions on the first 6% of salary. Only $4,500 (6% of $75,000) is matched, so the employer adds 50% × $4,500 = $2,250.
- Deposit and compound through the year. The $9,750 year total goes in as 12 deposits of $812.50 at the end of each month, while the balance earns 7% ÷ 12 a month. The $25,000 starting balance grows to $36,876.23 by the end of year 1.
- Raise the salary and repeat. Salary rises 3% a year, so contributions rise with it. In year 30 the salary is $176,742.41, you contribute $17,674.24 and the employer adds $5,302.27.
- Add up the result. At 65 the balance is $1,557,479.91: $25,000 to start, $356,815.62 of your contributions, $107,044.69 of employer contributions and $1,068,619.61 of investment growth.
How to read your result
The headline is the projected balance at your retirement age, before any tax. The figures below split it into your contributions, the employer’s contributions, investment growth and the starting balance, and the donut shows the same split. The year-1 contribution and match show the starting point of the plan.
The table lists salary, both contributions and the year-end balance for every year. When the IRS limit caps your contribution in some years, the result says how many; with a high salary and contribution rate, the cap can bind every year.
All amounts are in future dollars. A 3% raise and 7% return over 30 years make the final balance look large; the inflation calculator restates it in today’s dollars, and the retirement withdrawal calculator shows how long it could last.
What changes the result most
- Contribution rate
- Contributing 6% instead of 10% still earns the full match but lowers the balance at 65 to $1,140,689.92. Contributing 15% raises it to $2,078,467.41. The match is the same $107,044.69 in all three cases because it stops at 6% of salary.
- Return
- At 6% instead of 7%, the same contributions grow to $1,288,096.90, about $269,000 less. Over 30 years, one point of return changes the result more than any other input here.
- Years to retirement
- Starting at 45 instead of 35 with the same balance and salary gives $632,541.65 at 65, well under half of the 30-year result, because the last years of compounding add the most.
- IRS limits
- On a $200,000 salary with a 20% contribution, the limit caps your contribution in all 30 years: you put in $24,500 a year plus catch-up from age 50, $868,000 in total, and the balance is $3,754,608.16.
Questions
What is the 401(k) contribution limit for 2026?
The IRS limit on your own (elective) contributions is $24,500 for 2026. From age 50 you can add a catch-up of $8,000, and at ages 60, 61, 62 and 63 the catch-up is $11,250 instead. Employee plus employer contributions, excluding catch-up, cannot exceed $72,000 or 100% of pay.
How does an employer match work?
A common formula is a percentage of your contributions up to a share of salary, such as 50% of what you contribute on the first 6% of pay. On a $75,000 salary, contributing at least 6% ($4,500) earns the full $2,250 match; contributing 4% earns $1,500. Plans set their own formula and vesting rules.
Is the balance before or after tax?
Before tax. Traditional 401(k) withdrawals are taxed as ordinary income, so the spendable amount is lower than the balance shown. Roth 401(k) contributions are taxed going in, and qualified withdrawals are tax-free.
What is the catch-up contribution for ages 60 to 63?
Under SECURE 2.0, participants aged 60, 61, 62 and 63 can make a higher catch-up contribution: $11,250 for 2026, instead of the $8,000 available from age 50. The calculator uses your age at the start of each projection year to pick the amount.
More in Retirement
Sources
- IRS: 401(k) limit increases to $24,500 for 2026, IRA limit increases to $7,500 (IR-2025-111)
- IRS: 401(k) plan overview
- IRS: retirement topics, catch-up contributions
- Investor.gov compound interest calculator
These references explain the concepts behind the calculation. They do not endorse this site. Estimates leave out any cost or condition you did not enter.