About plusbeauxjours

This calculator answers one question: how much to put in each paycheck to max out your 401(k) in 2027, or in what's left of 2026. It handles the catch-up at 50, the larger catch-up at ages 60 to 63, the Roth catch-up rule for high earners, 27-paycheck years and the employer match.

How we keep it accurate

• Every number comes from an IRS publication or a named forecaster, with the date we checked it.
• Forecasts are labeled Projected until the IRS publishes the official figure.
• The day the IRS publishes the 2027 limits, we update the numbers, rerun our tests and note it in the changelog.
• The math is tested against worked examples, down to the cent.

Your privacy

Everything you enter is calculated in your browser. We don't ask for your name or email, and we don't send or store your inputs. Read the privacy policy (opens in a new tab) and terms (opens in a new tab).

Not advice

This is information, not investment, tax or legal advice. We are not affiliated with the IRS, any employer, plan administrator or brokerage. Your plan's rules decide what you can elect.

See all our tools at plusbeauxjours.com, or go back to the 401(k) calculator.