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ToolGrym

401(k) Calculator

Project your 401(k) balance at retirement with employer matching, annual raises, and compound growth — and see exactly how much of that future balance is your employer's money.

Written by Daniel Mercer, CFP® · Reviewed by Sarah Lindqvist, CFA

Last reviewed:

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Projected 401(k) at 65

$1,724,599

This year: you contribute
$5,600
This year: employer adds
$2,800
Lifetime employee contributions
$279,969
Lifetime employer match
$139,985

Balance by age

Projected 401(k) balance by age$0$500k$1M$1.5M30364248535965Age

What this calculator does

A 401(k) is three growth engines stacked: your contributions, your employer’s match, and compounding on both. This calculator runs all three year by year — with your salary rising over time — and reports the projected balance along with the line most statements never show: the lifetime total your employer contributed. For most careers, that match line is a five- or six-figure sum earned by nothing more than checking a box during onboarding.

How the math works

Each simulated year:

  1. You contribute your percentage of that year’s salary.
  2. The employer matches: salary × min(your %, match limit) × match rate.
  3. The balance compounds: balance × (1 + return) + both contributions.
  4. Salary grows by your raise assumption.

The projection is nominal (future dollars). For an inflation-adjusted view, the retirement calculator runs the same engine and deflates the result.

A worked example

Age 30, retiring at 65, current balance $25,000, salary $70,000, contributing 8% with a 100% match up to 4%, 7% returns, 2% raises.

Year one is easy to verify by hand: you contribute $5,600 (8% of 70,000); your employer adds $2,800 (100% of the first 4%). That $2,800 is an instant, risk-free 50% boost on your total contribution — before any market return.

Run the full 35 years and the employer’s side alone — $2,800 growing with raises and compounding at 7% — accumulates to roughly $486,000 of the final balance. Decline the match by contributing less than 4%, and that entire line item simply never exists.

Practical tips

  1. Never contribute below the match limit. It’s the highest-yield decision in personal finance: a 100% match is a guaranteed doubling of your money on day one. Whatever else your budget must sacrifice, capture the full match.
  2. Escalate 1% per year. Most plans offer automatic escalation. Moving from 8% to 12% one point at a time — ideally timed with raises — is barely felt in take-home pay and dramatically felt at 65. Change the contribution input here and watch.
  3. Check your vesting schedule. Your own contributions are always yours; employer match may vest over 3–6 years. If you’re months from a vesting cliff, the timing of a job change can be worth thousands.
  4. Mind fees inside the plan. A fund charging 0.8% versus 0.08% quietly consumes a meaningful slice of a 35-year balance. Most plans include at least one low-cost index or target-date option — the expense ratio is on the fund’s fact sheet.

The match is the headline

Everything else about 401(k)s — fund menus, Roth-versus-traditional, rollovers — matters less than two behaviors: contribute at least to the match limit, and don’t interrupt the compounding. This calculator exists mostly to make those two behaviors emotionally concrete: the match line shows what your employer pays you to save, and the chart shows what time does with it. For the tax-free sibling of this account, see the Roth IRA calculator; for whether the total is enough, the retirement calculator answers in today’s dollars.

Frequently asked questions

How does an employer match actually work?
Two numbers define it: the match rate and the limit. "100% match up to 4% of salary" means every dollar you contribute, up to 4% of your pay, is doubled. Contribute less than the limit and you receive proportionally less; contribute more and the excess is unmatched (but still grows tax-advantaged). Enter both numbers from your plan documents — they vary widely.
How much can I contribute to a 401(k)?
The IRS sets annual employee contribution limits, adjusted most years for inflation, with an additional catch-up allowance from age 50 (check the current figures on the IRS page linked below). Employer match money does not count against your employee limit — it has a separate, higher combined ceiling.
Traditional or Roth 401(k)?
Traditional contributions skip taxes now and pay them at withdrawal; Roth contributions pay taxes now and withdraw tax-free. The rough rule: expect a higher tax rate in retirement than today → Roth; lower → traditional. Either way the employer match is always contributed pre-tax. Model the Roth side with our Roth IRA calculator — the compounding math is identical.
What return should I assume?
A typical 401(k) menu's target-date or index funds have historically delivered portfolio returns in the 6–8% range over long horizons, before inflation. This calculator projects in nominal dollars — to see what the balance buys in today's money, cross-check with the inflation calculator or use the full retirement calculator, which deflates automatically.
What happens to my 401(k) when I change jobs?
Four options: leave it (if the balance is large enough), roll it into the new employer's plan, roll it into an IRA, or cash out. Cashing out before 59½ typically triggers income tax plus a 10% penalty and permanently removes the compounding you've built — almost always the worst choice. Also check your plan's vesting schedule: employer match money may only become fully yours after several years.

Written by

Daniel Mercer, CFP®

Daniel is a Certified Financial Planner™ with 12 years of experience helping households manage debt, savings, and retirement planning. He writes ToolGrym’s calculator guides and explains the math behind every tool.

Reviewed by

Sarah Lindqvist, CFA

Sarah is a CFA charterholder who reviews every ToolGrym calculator and article for mathematical accuracy. She has 10 years of experience in fixed-income analytics and consumer lending models.