Free Calculator
Roth vs. Traditional IRA Calculator
A simplified, side-by-side estimate of after-tax outcomes for Roth vs. Traditional contributions, based on your current and expected retirement tax brackets.
What this calculator actually does
It projects two after-tax outcomes from the same annual contribution amount: one assuming Traditional tax treatment (pre-tax now, taxed on withdrawal), one assuming Roth treatment (taxed now, tax-free on withdrawal) — then shows which comes out ahead after tax, given the rate assumptions you provide.
Assumptions built into the result
- Your current and retirement marginal tax rates are assumed to stay exactly as entered — actual future tax law and your future income are both unknowable in advance.
- It ignores state income tax, required minimum distributions, and changes to contribution limits over time.
- It compares a single contribution scenario, not a mix of account types over a career.
A worked example
Using the default values ($7,000/year, 30 years, 7% return, 22% current tax rate, 18% expected retirement tax rate): the Traditional path projects to roughly $583,600 after tax, versus roughly $555,100 after tax for Roth — Traditional comes out about $28,500 ahead in this specific scenario, because the assumed retirement tax rate (18%) is lower than the current rate (22%). Raise the assumed retirement rate above the current rate instead, and the result flips in Roth's favor — illustrating why this decision hinges entirely on a comparison you can't know with certainty in advance.
How this is calculated, and its limits
Traditional: the full contribution grows tax-deferred, then is taxed at your assumed retirement rate on withdrawal. Roth: the contribution is first reduced by your current tax rate (since Roth contributions are after-tax), then grows completely tax-free. This is a simplified model — it doesn't account for changing tax brackets over time, state taxes, required minimum distributions, or contribution limit differences. Consult a tax professional for your specific situation. See our methodology and disclaimer.
This calculator is a simplified educational estimate, not personalized tax advice. See our full disclaimer.