How to use this calculator
- Enter your current age, planned retirement age, salary, and expected annual raise.
- Enter the percent of pay you plan to contribute, then choose your employer's match schedule (or build a custom one).
- Enter your current 401(k) balance and expected annual return, plus an inflation rate to see your balance in today's dollars.
- Choose whether you're contributing pre-tax (Traditional) or Roth, and enter your current and expected retirement tax rates for the after-tax comparison.
- Review your projected balance, total employee and employer contributions, and growth. Check whether you're contributing enough to capture the full employer match, and see if any future year would exceed the 2026 IRS elective-deferral limit of $24,500.
How it's calculated
Each year, your contribution is salary × contribution %, capped at the IRS elective-deferral limit for your age that year (the 2026 base limit is $24,500, plus a $8,000 catch-up at age 50+, or a higher $11,250 catch-up at ages 60–63). Your employer's match is applied to the percentage you actually contribute after any cap, using your selected tier schedule (for example, "50% up to 6% of pay" matches half of your contribution up to 6% of salary).
Salary, your contribution, and the employer match are all capped at the annual compensation limit under Internal Revenue Code §401(a)(17) ($360,000 for 2026).
Contributions in a given year are assumed to be spread evenly through the year, so they earn about half a year's growth on average, while your starting balance earns a full year's growth at your expected annual return.
Your balance in today's dollars divides the projected balance at retirement by your inflation rate compounded over the years until retirement, so it reflects today's purchasing power.
IRS contribution limits are held flat at their 2026 amounts for every future year of the projection — they aren't inflated forward, since the IRS sets each year's limit separately based on that year's inflation data. Contribution limits IRS publishes only cover 2026; if the IRS raises limits in future years, your actual allowed contribution could be somewhat higher than shown here in years marked "capped."
The pre-tax vs. Roth comparison projects the identical dollar contributions and growth for both, then applies your retirement tax rate to the Traditional balance (since withdrawals are taxed as ordinary income) while the Roth balance is shown as-is (qualified Roth withdrawals are tax-free). It does not separately model investing the up-front tax savings from a Traditional contribution, or the fact that Roth contributions cost more take-home pay today at the same election percentage.
Assumptions
- This calculator assumes a constant annual return, salary growth rate, and contribution percentage every year — it doesn't model market volatility, job changes, contribution changes, or plan loans/withdrawals.
- Contribution limits (elective deferral, catch-up, and the compensation limit) are IRS figures for 2026 and are held flat for future projection years rather than assumed to grow with inflation.
- The employer match presets are common, illustrative schedules — check your plan's summary plan description for your actual match formula, vesting schedule, and any true-up provisions.
- The Roth vs. pre-tax comparison is a simplified illustration based on the tax rates you enter, not a personalized tax projection — actual outcomes depend on your full tax situation, future tax law, and state taxes.
- Results are estimates for planning purposes only and don't account for plan fees, required minimum distributions, or your complete financial picture — consult a qualified financial or tax professional for personalized advice.
Frequently asked questions
What is the 2026 401(k) contribution limit?
For 2026, the IRS elective-deferral limit is $24,500. Savers age 50 or older can contribute an additional $8,000 catch-up, and savers who are age 60, 61, 62, or 63 at any point during the year get a higher catch-up of $11,250 instead. These limits apply to your own elective deferrals and don't include employer contributions.
How does an employer 401(k) match work?
Most employers match a percentage of what you contribute, up to a cap expressed as a percent of your salary. For example, "50% up to 6%" means your employer adds 50 cents for every dollar you contribute, up to 6% of your pay — contributing less than 6% leaves part of that match unclaimed, often called "leaving free money on the table." Some plans use tiered formulas, such as matching 100% of the first 3% of pay and 50% of the next 2% (a common "safe harbor" design).
What are catch-up contributions, and how do the age 60–63 rules work?
Catch-up contributions let savers 50 and older contribute more than the standard limit. Starting in 2025, a new, higher catch-up applies specifically to savers who turn 60, 61, 62, or 63 during the year (it reverts to the regular age-50 catch-up at 64). This calculator applies the correct catch-up amount automatically based on your age in each projected year.
Roth 401(k) or Traditional (pre-tax) 401(k) — which is better?
It depends mainly on whether you expect your tax rate to be higher or lower in retirement than it is today. Traditional contributions reduce your taxable income now and are taxed as ordinary income when withdrawn; Roth contributions are made with after-tax money but qualified withdrawals in retirement are tax-free. This calculator shows both after-tax outcomes side by side using the tax rates you enter, but it can't predict future tax law or your personal tax bracket decades from now.
What happens if my contribution percentage would exceed the IRS limit?
The calculator automatically caps your dollar contribution at the IRS elective-deferral limit that applies to your age in each projected year, and flags any year where your elected percentage would have exceeded it. Your employer's match is then calculated on your actual (capped) contribution percentage, matching how most real plans handle a mid-year contribution cap.
Does the compensation limit affect my contribution or match?
Yes. The IRS also caps the salary used to calculate contributions and matching under Internal Revenue Code §401(a)(17) — $360,000 for 2026. If your salary is above this limit, both your contribution percentage and your employer's match are calculated on the capped amount, not your full salary.
Should I contribute enough to get the full employer match?
Employer matching contributions are effectively free money added to your retirement savings, so many savers prioritize contributing at least enough to capture the full match before directing additional savings elsewhere (like an IRA or a taxable account). This calculator flags when your contribution percentage falls short of your plan's full match.
How accurate is the 'balance in today's dollars' figure?
It divides your projected nominal balance at retirement by your inflation rate compounded over the years until retirement, showing what that balance would be worth in today's purchasing power. It's a standard, simple inflation adjustment — it doesn't attempt to predict actual future inflation, which will vary year to year.
Can I model a 401(k) with no employer match?
Yes — choose "No employer match" from the match schedule menu. The calculator will then project growth from your own contributions and investment returns alone, with no employer contribution amount.
Does this calculator account for vesting schedules?
No. It assumes 100% of the employer match shown becomes yours. Many employer matching contributions vest gradually over several years of service — check your plan documents for your vesting schedule, since you may forfeit unvested employer contributions if you leave before becoming fully vested.
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Disclaimer: This calculator provides estimates for educational purposes only and is not financial, tax, or legal advice or an offer of credit. Actual payments depend on your lender, loan terms, taxes, and insurance. Consult a qualified professional before making financial decisions.