Roth vs Traditional 401(k) Calculator
Compare Roth and traditional 401(k) outcomes side by side: tax savings now vs tax-free withdrawals later, at your actual bracket. Free, instant, private.
Roth or traditional is really one question: do you pay taxes at today's rate or at your future rate? This calculator runs your salary, contribution, and current bracket against retirement withdrawal assumptions, and shows the after-tax outcome of each path — including what happens if you invest the tax difference.
The break-even is personal: early-career savers usually win with Roth, peak earners with traditional, and most people are best served splitting contributions. See the actual numbers for your situation instead of guessing.
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401(k) vs Roth IRA
Side-by-side comparison with growth curves — drag sliders to see which wins for you.
2026 401(k) contribution limit: $24,500 ($32,500 if age 50+; $8,000 catch-up). Roth contributions are post-tax; Traditional are pre-tax. Investment returns assumed at 7% nominal. This is for estimation only — consult a financial advisor.
Traditional vs. Roth tax treatment — illustrated
This tool compares the after-tax value at retirement of a Traditional 401(k) and a Roth IRA by applying the same pre-tax annual contribution to both. The only difference is when you pay tax: Traditional defers it to withdrawal (taxed at your retirement bracket), Roth pays it upfront (taxed at your current bracket) so withdrawals come out tax-free. After N years at return r, Traditional nets roughly (1 − retirementRate) × growth while Roth nets (1 − currentRate) × growth, so the winner is whichever bracket is lower. With 2026 limits — $24,500 for a 401(k), $7,500 for an IRA, $8,000 catch-up at 50+ — the same dollars behave very differently depending on your marginal rate today versus in retirement.
Same pre-tax salary dollars, same 30-year growth at 7%. Traditional defers the tax to withdrawal; Roth collects it on the way in and lets the growth exit free.
Priya is 35, in the 24% federal bracket today, and expects to be in the 18% bracket at retirement. She can save the full 2026 401(k) limit of $24,500/year, contributing the same pre-tax amount to either a Traditional 401(k) or a Roth IRA for 30 years at 7%.
- Contribution:Traditional: $24,500 pre-tax. Roth: only $18,620 post-tax reaches the account (24% × $24,500 is paid today).
- Growth over 30 yrs at 7%:Traditional grows to about $2.31M; Roth to about $1.76M — the tax you paid upfront compounds away.
- Tax at withdrawal (18%):Traditional owes roughly $416,000 when withdrawn; Roth owes $0.
- Net at retirement:Traditional ≈ $1.90M vs. Roth ≈ $1.76M — Traditional wins by ~$139K because today’s 24% exceeds retirement’s 18%.
About this Roth vs traditional 401k calculator
This page covers should i do roth or traditional 401k, roth 401k vs pretax calculator, roth ira vs 401k which is better, pre tax vs roth comparison — all the same underlying task as Roth vs traditional 401k calculator. The tool above is FreeToolHub's 401k vs roth embedded in full: every feature works right here, and nothing you process is uploaded to any server.
Frequently asked questions
Is Roth 401(k) better than traditional?
It depends on your marginal tax rate now versus in retirement. Roth wins when your future rate is higher — typical for early-career workers — while traditional wins for peak earners. A common strategy is traditional enough to capture any employer match and lower your bracket, Roth for the rest. Run your numbers; the crossover point is different at every salary.
Does the employer match count as Roth?
Employer matching contributions are always pre-tax (traditional), even if your own contributions are Roth — at least until SECURE 2.0's optional Roth match rolls out where employers choose to offer it. The calculator treats the match as pre-tax automatically.