Compare pre-tax and after-tax retirement saving on your own tax rates — including the side fund a deduction buys.
Roth advantage
$3,020
After-tax difference at retirement.
Tax savings invested taxably.
Contributing $7,000 a year for 30 years at 7% grows to $661,226 in either account. The Roth is yours tax-free: $661,226. The traditional is taxed at 22% on withdrawal ($515,756) but its deduction frees $1,680 a year to invest on the side, worth $142,450 after tax — $658,206 combined.
A Roth wins when your retirement tax rate is higher than today's — you pay tax at the lower rate now. Traditional wins when your retirement rate is lower — you defer tax to a cheaper time. At 24% now versus 22% later, traditional has the edge on rates alone. The catch is that nobody knows future tax rates, which is why many people split contributions between both.
Beyond the arithmetic, a Roth has no required minimum distributions in your lifetime, gives tax-free income that doesn't inflate your taxable income in retirement (which can affect Medicare premiums and Social Security taxation), and passes to heirs tax-free. Those are real benefits that a pure rate comparison misses — worth weighting toward the Roth when the numbers are close.
See the detail behind each option — the Roth's tax-free growth, or your 401(k)'s employer match — with the dedicated calculators.
Roth IRA calculatorWorked scenarios with the full analysis, so you can see how the numbers move before entering your own.
When your tax rate doesn't change, the two are close to a wash — the tiebreakers are flexibility and RMDs.
Roth advantage
$16,244
Contributing $7,000 a year for 30 years at 7% grows to $661,226 in either account. The Roth is yours tax-free: $661,226. The traditional is taxed at 24% on withdrawal ($502,531) but its deduction frees $1,680 a year to invest on the side, worth $142,450 after tax — $644,981 combined.
A Roth wins when your retirement tax rate is higher than today's — you pay tax at the lower rate now. Traditional wins when your retirement rate is lower — you defer tax to a cheaper time. At 24% now versus 24% later, the two are nearly a wash on rates alone. The catch is that nobody knows future tax rates, which is why many people split contributions between both.
Beyond the arithmetic, a Roth has no required minimum distributions in your lifetime, gives tax-free income that doesn't inflate your taxable income in retirement (which can affect Medicare premiums and Social Security taxation), and passes to heirs tax-free. Those are real benefits that a pure rate comparison misses — worth weighting toward the Roth when the numbers are close.
A high earner today expecting a lower bracket in retirement, favoring the traditional deduction.
Traditional advantage
$31,423
Contributing $7,000 a year for 25 years at 7% grows to $442,743 in either account. The Roth is yours tax-free: $442,743. The traditional is taxed at 22% on withdrawal ($345,340) but its deduction frees $2,240 a year to invest on the side, worth $128,826 after tax — $474,166 combined.
A Roth wins when your retirement tax rate is higher than today's — you pay tax at the lower rate now. Traditional wins when your retirement rate is lower — you defer tax to a cheaper time. At 32% now versus 22% later, traditional has the edge on rates alone. The catch is that nobody knows future tax rates, which is why many people split contributions between both.
Beyond the arithmetic, a Roth has no required minimum distributions in your lifetime, gives tax-free income that doesn't inflate your taxable income in retirement (which can affect Medicare premiums and Social Security taxation), and passes to heirs tax-free. Those are real benefits that a pure rate comparison misses — worth weighting toward the Roth when the numbers are close.
A younger saver early in their career expecting to earn more later, favoring the Roth.
Roth advantage
$129,127
Contributing $7,000 a year for 35 years at 7% grows to $967,658 in either account. The Roth is yours tax-free: $967,658. The traditional is taxed at 24% on withdrawal ($735,420) but its deduction frees $840 a year to invest on the side, worth $103,111 after tax — $838,531 combined.
A Roth wins when your retirement tax rate is higher than today's — you pay tax at the lower rate now. Traditional wins when your retirement rate is lower — you defer tax to a cheaper time. At 12% now versus 24% later, the Roth has the edge on rates alone. The catch is that nobody knows future tax rates, which is why many people split contributions between both.
Beyond the arithmetic, a Roth has no required minimum distributions in your lifetime, gives tax-free income that doesn't inflate your taxable income in retirement (which can affect Medicare premiums and Social Security taxation), and passes to heirs tax-free. Those are real benefits that a pure rate comparison misses — worth weighting toward the Roth when the numbers are close.
Decades of compounding, where the Roth's tax-free growth has the most to work with.
Roth advantage
$86,870
Contributing $7,000 a year for 40 years at 8% grows to $1,813,396 in either account. The Roth is yours tax-free: $1,813,396. The traditional is taxed at 24% on withdrawal ($1,378,181) but its deduction frees $1,540 a year to invest on the side, worth $348,345 after tax — $1,726,526 combined.
A Roth wins when your retirement tax rate is higher than today's — you pay tax at the lower rate now. Traditional wins when your retirement rate is lower — you defer tax to a cheaper time. At 22% now versus 24% later, the Roth has the edge on rates alone. The catch is that nobody knows future tax rates, which is why many people split contributions between both.
Beyond the arithmetic, a Roth has no required minimum distributions in your lifetime, gives tax-free income that doesn't inflate your taxable income in retirement (which can affect Medicare premiums and Social Security taxation), and passes to heirs tax-free. Those are real benefits that a pure rate comparison misses — worth weighting toward the Roth when the numbers are close.
Traditional and Roth accounts are mirror images. A traditional IRA or 401(k) gives you a tax deduction today, grows tax-deferred, and is taxed as ordinary income when you withdraw. A Roth gives no deduction today, but grows and withdraws entirely tax-free. Both have the same contribution limits, and both are far better than an ordinary taxable account.
The decision reduces to one comparison: is your tax rate higher now or in retirement? If higher now, the traditional deduction is worth more, and you'll pay tax later at a lower rate. If higher later, the Roth wins because you lock in today's cheaper rate. Since nobody knows future rates, many savers deliberately hold both to hedge.
A common flaw in traditional-vs-Roth comparisons is ignoring what the traditional deduction buys you. If contributing to a traditional account saves you $1,680 in tax this year, that money is real — and a fair comparison assumes it gets invested rather than spent. This calculator models it as a taxable side fund, with its growth taxed at long-term capital gains rates at the end.
Beyond the arithmetic, the Roth carries structural advantages: no required minimum distributions in your lifetime, tax-free income that doesn't push up your taxable income in retirement (which can affect Medicare premiums and how much of your Social Security is taxed), and tax-free inheritance for heirs. When the pure numbers are close, those tip the balance toward the Roth.
A traditional contribution frees cash today. A fair comparison invests that saving rather than pretending it doesn't exist.
Many retirees aren't in a lower bracket, especially with RMDs and Social Security. Don't assume rates fall automatically.
Traditional accounts force taxable withdrawals from 73. Roth accounts don't, which matters for flexibility and heirs.
Nobody knows future tax rates. Holding both gives you flexibility to draw tax-efficiently in retirement.
Direct Roth contributions phase out at higher incomes. Check eligibility, or consider a backdoor Roth.
Compare your tax rate now to your expected rate in retirement. If you expect a higher rate later — common for younger savers early in their careers — the Roth wins. If you expect a lower rate, the traditional deduction wins. When they're close, the Roth's lack of required distributions and tax-free inheritance often tip the balance.
Usually yes. Younger workers are often in lower tax brackets than they'll be later, so paying tax now at a low rate and never again is advantageous. They also have the longest time horizon, which maximizes the value of decades of tax-free compounding. That said, if you're currently in a high bracket, a traditional deduction may still win.
Yes, but the annual limit is shared across both — you can split it however you like, not double it. Many savers deliberately hold both types to hedge against uncertain future tax rates, giving them flexibility to draw from whichever is more tax-efficient in a given retirement year.
Only if you invest it. A traditional contribution reduces this year's tax bill, and a fair comparison assumes that saving is invested rather than spent. This calculator models it as a taxable side fund. If you'd spend the tax savings instead, the Roth becomes clearly better — which is a real argument for the Roth's forced discipline.
Traditional IRAs and 401(k)s require you to start withdrawing at age 73, whether you need the money or not, and those withdrawals are taxable. Roth IRAs have no RMDs during the owner's lifetime, so the money can keep growing tax-free indefinitely — a meaningful advantage for anyone who may not need to spend it all.
The next calculations that usually follow this one.
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Guides that explain the decisions behind these numbers.
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