Taly Tools
Free tool · Retirement

Roth vs. Traditional Calculator

Pre-tax or after-tax — which leaves you more money to actually spend in retirement? Compare a Roth and a Traditional contribution on an honest, after-tax basis, and see the one number that decides it: the break-even retirement tax rate.

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Roth vs. Traditional, decided by one number

Both accounts get the same tax break — just at different times. A Traditional contribution is deducted from your income today and grows tax-deferred; you pay income tax on every dollar you withdraw in retirement. A Roth contribution is made with money you've already paid tax on, and then grows and comes out completely tax-free.

Because of that symmetry, the entire decision collapses to a single comparison: your marginal tax rate now versus in retirement. Pay the tax when your rate is lowest. If you expect to be in a higher bracket later, Roth's pay-now deal wins; if you expect a lower bracket, Traditional's defer-now deal wins.

This calculator makes the comparison fair. Putting $7,000 into a Roth costs more out of pocket than $7,000 into a Traditional account, because the Roth dollars are already taxed. So it can invest Traditional's up-front tax savings in a taxable side account — capital-gains drag and all — so both paths use the same budget. Then it solves for the break-even retirement tax rate: the rate at which the two paths leave you with exactly the same after-tax money.

  • Above the break-even rate: Roth comes out ahead — paying tax now, while it's cheap, locks in tax-free growth.
  • Below it: Traditional wins — deferring tax at a high rate and paying it later at a lower one keeps more.

Two things the dollar math doesn't price, both pointing toward Roth: a Roth IRA has no required minimum distributions in your lifetime, so it can keep compounding untouched — and Roth is a hedge against future tax-rate increases, since you've already settled the bill at today's known rate.

Common questions

Is a Roth or a Traditional account better for me?
It hinges on your marginal tax rate now versus in retirement. Enter both rates (or estimate them from your income), and the calculator tells you which path leaves more after-tax money — and the exact break-even retirement tax rate where they tie. If you expect a higher bracket later, Roth tends to win; lower, Traditional.
What about contribution limits?
Limits are shown for reference but don't cap the math — so you can compare any contribution amount apples-to-apples. For 2025, that's $7,000 into an IRA and $23,500 of 401(k) elective deferral, plus catch-up contributions if you're 50 or older. Check the current year's limits before you contribute.
Is anything saved or sent anywhere?
No. Every number runs in your browser. Nothing you type is uploaded, stored, or shared — and you can export the full year-by-year table to CSV with one click.

Finding the money to contribute is the hard part

Taly auto-splits every paycheck across your budget — so the room to fund a Roth or Traditional account shows up on its own, instead of you hunting for it. Your paycheck does the math.