Short answer: your 401(k) outcome is driven less by investment picks than by two numbers — your contribution rate and whether you capture the full employer match. Example below: on an $85,000 salary, contributing 10% with a typical 50%-of-6% match builds a projected $1,871,015 by 65; the match alone accounts for $319,391 of it. Run your own salary and match formula — every plan’s match is different, and most calculators won’t let you enter yours.
Show the math
Your numbers, one step at a time. The starting balance, contributions, match and growth add up to the headline.
Year-by-year breakdown (your plan vs the higher-contribution plan)
| Age | Your plan | Higher contribution |
|---|
Educational estimate only — not financial advice. Assumes contributions and match are deposited monthly, salary grows once a year, and the return is smooth — real markets are not. It does not cap contributions at the IRS limit or model catch-ups beyond the limit shown, loans, fees or taxes. Your numbers never leave this page: all math runs in your browser.
Sources: IRS IR-2025-111 (2026 401(k) limit $24,500; catch-up $8,000 at 50+; $11,250 at ages 60 to 63) Figures last verified Report a wrong number
How this calculator works
Enter your age, salary, current balance, and contribution rate. Then enter your employer’s actual match formula — the match percentage and the salary cap it applies to (for example, “50% of what you contribute, up to 6% of salary”). Deposits and match are added monthly, salary grows once a year, and growth compounds monthly at your assumed return. Formulas: monthly contribution = salary ÷ 12 × your %; monthly match = min(your contribution, salary ÷ 12 × cap %) × match %. The comparison line re-runs everything at a higher contribution rate so you can see exactly what an extra 1–3% buys. The “value of the match” re-runs your plan with the match switched off — the difference is what the match is worth. Assumptions: smooth returns (real markets zigzag), no fees, no loans, no taxes, and no IRS contribution limits or catch-ups — check yours at irs.gov if you contribute near the max.
Worked example
Age 35, salary $85,000 growing 2% a year, $60,000 already saved, contributing 10%, employer matches 50% up to 6% of salary, 7% return: – Projected balance at 65: $1,871,015 – You contribute $344,829 of it; the match adds $103,449 in deposits – Without the match, the same plan ends $319,391 poorer — that’s the match’s true value after 30 years of compounding – Contributing 13% instead: $2,190,406 (+$319,391)
FAQs
How much should I contribute to my 401(k)? At minimum, enough to get the full employer match — that’s an instant 50–100% return no market reliably beats. Beyond that, the right rate depends on your other debts, taxes, and goals; the comparison line shows what each extra percent buys. What is a typical employer match? A common formula is 50% of the first 6% of salary you contribute (worth 3% of salary), but formulas vary widely — check your plan document or HR portal for yours. Does this include the IRS limit? No. The IRS caps elective deferrals (the 2026 limit is $24,500 under 50, plus an $8,000 catch-up at 50+) — verify the current limit at irs.gov if you’re a high contributor. Why is the match worth more than the match deposits? Because matched dollars compound too. In the example, $103,449 of match deposits becomes $319,391 of final balance.
Disclaimer
Educational content only — not financial, tax, or investment advice. Projections are hypothetical, use assumed smooth returns, and are not a guarantee of any outcome.