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Pre-tax now vs tax-free later

Traditional vs Roth 401(k) Calculator

Should you pay tax now (Roth) or later (Traditional)? It mostly comes down to your tax bracket today versus in retirement. Compare the after-tax value of each, side by side.

Your details

$
Pre-tax dollars you'd put in.
183570
406575
1%7%12%
Assumption.
%
Your marginal bracket today.
%
Expected future bracket.

After-tax comparison

Likely winner
Roth 401(k)
  • Roth 401(k) after tax$91,347
  • Traditional 401(k) after tax*$89,136
  • Difference$2,211
* Traditional figure assumes you invest the up-front tax saving in a taxable account, so the comparison is apples-to-apples on equal take-home pay.

Figures current for 2026 · last reviewed June 2026 · sourced from the IRS (IRS Notice 2025-67). How we calculate & cite our data. Educational only — not financial advice.

Assumptions & notes

The simple rule of thumb
If you expect a HIGHER tax rate in retirement than today, Roth usually wins (pay tax now at the lower rate). If you expect a LOWER rate later, Traditional usually wins. When the rates are equal, they're nearly identical.
Why the side account?
A Roth contribution is after-tax, so on equal take-home pay a Traditional saver has extra cash today (the tax they didn't pay). To compare fairly we invest that saving in a taxable account and tax its growth. Without it, Roth looks artificially better.
Other reasons to choose Roth
Roth 401(k) withdrawals are tax-free, have no required minimum distributions for Roth IRAs, and hedge against future tax-rate increases. Many savers split contributions between both for flexibility.
These are assumptions, not guarantees. Investment returns and inflation are estimates you control - markets vary and past performance does not predict future results. Tax figures use current-year IRS numbers; your situation may differ. This tool is educational and not financial advice.

Traditional vs Roth 401(k), explained

A Traditional 401(k) gives you a tax deduction today and grows tax-deferred; you pay ordinary income tax when you withdraw in retirement. A Roth 401(k) is the mirror image: you contribute after-tax dollars now, and qualified withdrawals - including all the growth - are completely tax-free.

Younger savers early in their careers, anyone expecting higher future tax rates, and those who value tax-free flexibility often lean Roth. High earners in their peak years who expect to drop into a lower bracket in retirement often prefer the up-front Traditional deduction. Because nobody knows future tax law, splitting contributions is a popular hedge.

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For educational purposes only — not financial, tax or investment advice. Results are estimates based on the inputs and assumptions you provide and current IRS figures; they are not a guarantee of future results. Verify limits with the IRS and consult a qualified professional before acting.

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