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401(k) Contribution Calculator

See your annual contributions, employer match, paycheck impact, and projected balance at retirement.

Total going in yearly$9,900

Understanding this calculator

Two numbers do most of the work in a 401(k): your contribution percentage and your employer's match formula. The match is the closest thing to free money in personal finance — contributing below the match limit leaves part of your compensation on the table every payday, and this calculator will show you exactly how much.

The paycheck impact is usually smaller than people fear. Traditional contributions come out before income tax, so a $500 contribution might only shrink take-home pay by $380 or so, depending on your bracket. If you're 50 or older the limits rise, and at ages 60–63 the SECURE 2.0 "super catch-up" raises them further.

Assumptions and methodology

  • 2026 IRS limits: $24,500 employee deferral; catch-up $8,000 at 50+; $11,250 at ages 60–63 (IR-2025-111).
  • Employer match modeled as a single tier: match rate applied to your contribution up to a percent of salary.
  • Take-home impact = contribution minus estimated tax savings at the marginal rate you select; FICA still applies to deferrals.
  • Projection compounds monthly at your chosen return until your retirement age; salary growth and limit inflation are not modeled.
  • High earners: the 2026 rule requiring catch-ups to be Roth for prior-year FICA wages over $145k (indexed) isn't modeled.

Last reviewed August 30, 2026. Year-specific figures show their tax or data year in the tool; data is reviewed when the IRS, SSA, and CMS publish annual updates.

Common questions

How much should I contribute?

At minimum, enough to capture the full employer match. Beyond that, 10–15% of pay including the match is a common lifetime guideline — more if you started late.

Traditional or Roth 401(k)?

Same logic as the IRA question — compare today's rate with your expected retirement rate. Our Traditional vs. Roth calculator walks through it.