SlickCalc

401(k) Calculator

Estimate your 401(k) balance at retirement. Adjust contribution rate, employer match, and expected return to see how much you'll have and what changes the most.

Your 401(k)

Most workers contribute 5-15% of salary. 2026 IRS limit: $24,500 (under 50) or $32,500 (50+ with catch-up).

Results

Balance at age 65

$1,956,265

Your Total

$374,959

Employer Match

$112,488

Investment Return

$1,458,819

Balance Breakdown

Total Contributions$497,446
Investment Return$1,458,819
AgeSalaryContributionBalance
31$75,000$9,750$20,851
32$76,500$9,945$32,688
33$78,030$10,144$45,588
34$79,591$10,347$59,631
35$81,182$10,554$74,905
36$82,806$10,765$91,501
37$84,462$10,980$109,521
38$86,151$11,200$129,072
39$87,874$11,424$150,269
40$89,632$11,652$173,236
41$91,425$11,885$198,104
42$93,253$12,123$225,018
43$95,118$12,365$254,129
44$97,021$12,613$285,601
45$98,961$12,865$319,611
46$100,940$13,122$356,346
47$102,959$13,385$396,009
48$105,018$13,652$438,818
49$107,118$13,925$485,005
50$109,261$14,204$534,820
51$111,446$14,488$588,532
52$113,675$14,778$646,427
53$115,948$15,073$708,814
54$118,267$15,375$776,025
55$120,633$15,682$848,414
56$123,045$15,996$926,361
57$125,506$16,316$1,010,276
58$128,016$16,642$1,100,596
59$130,577$16,975$1,197,790
60$133,188$17,314$1,302,364
61$135,852$17,661$1,414,857
62$138,569$18,014$1,535,849
63$141,341$18,374$1,665,962
64$144,167$18,742$1,805,862
65$147,051$19,117$1,956,265

How a 401(k) Grows

A 401(k) is an employer-sponsored retirement account where you contribute a percentage of each paycheck, and many employers add a 'match' on top — free money for choosing to save. Your contributions grow tax-deferred (Traditional 401(k)) or tax-free in retirement (Roth 401(k)), and the balance compounds for decades. This calculator projects the balance forward using monthly compounding on whatever annual return assumption you enter — the long-run average for a stock-heavy 401(k) portfolio is typically modeled at 6-8% after inflation.

The employer match is the highest-return part of your 401(k) and you should always contribute at least enough to get the full match. A common structure is '50% match up to 6% of salary' — meaning if you contribute 6% of your salary, your employer adds another 3%, an instant 50% return. The 'Match Limit' field in this calculator caps the matched amount at a percentage of salary: contributing more than that still adds to your balance but stops earning a match. The IRS sets total 401(k) limits separately ($24,500 employee for 2026, plus $8,000 catch-up at age 50+).

Time horizon matters more than the contribution rate for most people. A 25-year-old contributing $200/month at 7% return ends up with more than a 45-year-old contributing $500/month, because compounding works exponentially. The biggest mistakes are (1) not contributing enough to get the full employer match, (2) cashing out the 401(k) when changing jobs instead of rolling it over, and (3) being too conservative — bond-heavy allocations underperform stocks over multi-decade horizons.

Want to compare to other accounts? An investment calculator shows untaxed account growth, compound interest explains the math, and our salary calculator shows your take-home pay after 401(k) deductions reduce your taxable income.

Frequently Asked Questions

How much will my 401(k) be worth at retirement?
Depends on three things: how much you contribute each year, your employer match, and your investment return. As a rough benchmark, contributing 10% of a $75,000 salary with a 3% employer match and a 7% annual return for 35 years produces about $1.2-1.4 million at retirement. Use this calculator with your own numbers — small changes in contribution rate or return assumption compound dramatically over decades.
What is the 2026 401(k) contribution limit?
For 2026, employees can contribute up to $24,500 of their own money to a 401(k). If you're 50 or older, you can contribute an additional $8,000 'catch-up,' for a total of $32,500. The total of employee + employer contributions is capped at $72,000 ($80,000 with catch-up). These limits are set by the IRS and updated annually for inflation.
How does employer matching work?
The most common formula is '50% match up to 6% of salary,' meaning your employer puts in 50 cents for every dollar you contribute, but only matches contributions up to 6% of your salary. On a $75,000 salary, if you contribute 6% ($4,500), the employer adds 3% ($2,250). Contribute less and you leave free money on the table — always contribute at least enough to get the full match.
What's a realistic annual return to use?
The S&P 500 has averaged about 10% nominal (7% after inflation) over the long run. Most retirement projections use 6-8% to be slightly conservative. If you're heavily in bonds or near retirement, use 4-5%. If you're 100% in stocks and young, 8% is reasonable. Don't use 10%+ — that's the headline average but ignores volatility, fees, and the risk you retire during a downturn.
Should I contribute to a Traditional or Roth 401(k)?
Traditional 401(k) lowers your taxable income now and you pay taxes on withdrawals in retirement. Roth 401(k) is funded with after-tax money and grows tax-free. Rule of thumb: choose Traditional if you expect to be in a lower tax bracket in retirement (most people late in their career), choose Roth if you expect to be in a higher bracket (early career, fast-growing income, or in a low-tax state planning to retire elsewhere). Many people split contributions to hedge tax-rate uncertainty.
Can I contribute too much?
Yes — exceeding the IRS limit ($24,500 in 2026) creates a tax penalty. Most employers and payroll systems auto-cap your contribution at the IRS limit, but if you switch jobs mid-year you can accidentally exceed it across two employers. Track your year-to-date total in early December. If you're already maxed at 50+, also consider opening an IRA or HSA for additional tax-advantaged room.

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