Retirement account optimizer: 401(k), Roth, and IRA strategy

• Every pre-tax contribution (Traditional 401(k) or IRA) reduces this year's taxable income at your current tax bracket, so the calculator multiplies your pre-tax contributions by that bracket to show the immediate tax savings.
• Each account's balance is projected forward to your retirement age using a 7% assumed annual return, compounding on both the current balance and future contributions.
• It flags a 401(k) that lists a match but no contribution. The lab does not know your plan's match formula, so check it with your plan administrator.
• It checks whether you hold both pre-tax and Roth (post-tax) money, because having both gives you a choice of which bucket to draw from once your tax bracket in retirement becomes clearer.

The 2026 employee 401(k) limit is $24,500, plus an extra $8,000 catch-up if you're 50 or older ($32,500 total). If you're in the 24% bracket and contribute the full $24,500 pre-tax, that lowers this year's tax bill by $5,880. That's the immediate benefit; the account still owes ordinary income tax when you withdraw it in retirement, which is the trade-off a Roth account doesn't have.

• Balances grow at a flat 7% annual return for every account type, which won't match any single year's real market performance.
• The tax-savings figure uses only your current federal marginal bracket. It ignores state tax, and it ignores that a large pre-tax contribution can itself push you into a different bracket.
• Contribution limits shown in this tool reflect the account type you pick; check them against the current-year IRS limits before assuming they're up to date.
• It doesn't account for required minimum distributions, Social Security taxation, or Medicare IRMAA surcharges, all of which affect which account you'll wish you'd used.

Finance Quest is educational. It is not financial advice, and no calculator here knows your full situation.

An employer match is an immediate return that few investments can offer, though some plans make you stay for a vesting period before it is yours. If your employer matches 50% up to 6% of pay and you put money into an IRA instead of reaching that 6% in your 401(k), you pass on the match to get a tax break the 401(k) offers too. Many people reach the match first and then decide where the rest goes.

• Roth IRA vs traditional IRA: what is the difference?When each account is taxed, the 2026 limits, and a bracket example.
• How do you open your first Roth IRA?Who qualifies, where to open one, what to buy, and the deadline.

• Roth conversionWeigh tax owed now against tax-free growth later on a conversion.
• Withdrawal strategyTest a withdrawal rate, the 4% rule included, against a bad first decade.
• Tax deductionsCompare standard against itemized on your real numbers.