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401k Calculator

Project your 401k at retirement, including the employer match and salary growth, and see what vesting could cost you if you leave early.

Contribution inputs

Balance at retirement

Balance at retirement -
Your contributions -
Employer match -
Investment growth -

Estimate only. Not a substitute for your plan's own projection tool.

Why the match is the highest guaranteed return in the plan

A 50% match up to 6% of salary turns every dollar you defer, up to that limit, into a dollar fifty the moment it lands in your account. No investment carries that kind of guaranteed, immediate return. Skipping it to keep more of your paycheck is the single most expensive mistake this calculator can help you avoid.

Rule of thumb: contribute at least enough to capture the full match before you route extra savings anywhere else, including a Roth IRA. The match usually wins on pure arithmetic.

The numbers this calculator uses

IRS 401(k) limits referenced on this page
LimitAmountTax year
Employee elective deferral$24,5002026
Catch-up contribution, age 50+$8,0002026
Catch-up contribution, age 60 to 63$11,2502026

Source: IRS Notice 2025-67, Nov. 13, 2025. Contribution limits are set annually, usually announced each fall for the following year, so confirm the current figure at irs.gov/retirement-plans/401k-plans before you set next year's deferral.

Vesting: the part employers don't put in the offer letter

Your own contributions are always fully yours from day one. The match is a different story. Federal rules cap how slowly an employer can vest it: either a three-year cliff, where you own 0% of the match balance until your third anniversary and then jump to 100%, or a graded schedule spread across two to six years. Change jobs before you clear that schedule and the unvested portion of the match reverts to the employer, not to you. If a job offer is close and vesting timing matters, ask HR for the exact schedule in writing rather than assuming the plan-wide default applies.

If you are weighing this plan against saving in an IRA instead, the Roth vs Traditional IRA comparison uses the same salary and return fields and is a natural next stop once you know your match is locked in. For the drawdown side of the picture once you retire, see the retirement calculator.

Good to know

FAQs

How does vesting affect what I actually keep if I leave my job early?

Your own contributions are always 100% yours. The employer match is often subject to a vesting schedule, commonly a three-year cliff (you keep 0% before three years, then 100%) or a graded schedule spread over two to six years. Leave before you are fully vested and you forfeit the unvested part of the match, though not your own money.

What happens to the employer match if I stop contributing partway through the year?

Most plans match contributions as they happen, so the match simply stops when your contributions stop. A few plans true up at year end to make sure you got the full match you were entitled to based on annual pay, but that is a plan-specific feature, not a given. Check your plan document.

Can I still receive a match on contributions above the annual deferral limit?

No. Once your own contributions hit the IRS deferral limit for the year, payroll stops deducting them, and a plan can only match contributions that were actually made. If you front-load contributions early in the year and hit the cap before December, you can lose match dollars on paychecks after that unless your plan trues up.

Does this calculator factor in the age-50 catch-up contribution automatically?

No, the tool models your contribution as a percentage of salary rather than a flat catch-up dollar amount. If you are 50 or older and want to model a catch-up, raise the contribution percentage field until your annual dollar contribution matches what you actually plan to defer, including the catch-up.

What return assumption is reasonable for a target-date or index-fund 401k?

Plenty of long-range plans use something in the 6 to 7 percent range for a stock-heavy mix, before adjusting for inflation. Your own plan's fund menu, fee levels, and asset mix will move that number in either direction, so treat any single figure as a placeholder to stress-test, not a promise.