401(k) Calculator
Project your 401(k) balance at retirement using 2026 IRS contribution limits, real Fidelity employer match data, and historical market returns. Includes the SECURE 2.0 Roth catch-up warning for high earners and Fidelity\'s age-based benchmarks.
Last updated: April 2026 · Sources: IRS Notice 2025-67, Fidelity Q4 2025 Retirement Analysis
7% is standard real return
2026 401(k) limits and what changed
The IRS announced the 2026 retirement plan contribution limits in Notice 2025-67 on November 13, 2025. The standard 401(k) employee contribution limit increased to $24,500 (up $1,000 from $23,500 in 2025). Workers age 50 and older can add an $8,000 catch-up contribution, bringing their total to $32,500. Workers ages 60 through 63 get a higher "super catch-up" of $11,250 under SECURE 2.0, for a total of $35,750.
The combined limit on employee plus employer contributions to a 401(k) is now $72,000 for 2026 (up from $70,000 in 2025). This cap is what allows highly compensated employees to make after-tax contributions and mega-backdoor Roth conversions if their plan supports it.
The biggest 2026 change is the SECURE 2.0 Roth catch-up rulefor high earners. Starting January 1, 2026, anyone age 50+ who earned more than $150,000 in FICA wages in the prior year must make their catch-up contributions on a Roth (after-tax) basis — not pre-tax. The IRS finalized these regulations on September 16, 2025. If your employer\'s 401(k) plan does not offer a Roth option, high earners may lose access to catch-up contributions entirely until the plan adds one.
Average 401(k) balances by generation (Fidelity Q4 2025)
| Generation | Birth years | Average 401(k) | Median 401(k) |
|---|---|---|---|
| Gen Z | 1997-2012 | $17,900 | ~$5,900 |
| Millennial | 1981-1996 | $83,700 | ~$27,800 |
| Gen X | 1965-1980 | $222,100 | ~$74,000 |
| Boomer | 1946-1964 | $270,800 | ~$90,000 |
| All ages | - | $146,400 | $34,400 |
Source: Fidelity Investments Q4 2025 401(k) data based on 24.8 million corporate plan participants. Median estimated as ~1/3 of average per Vanguard methodology. The all-ages average has been pulled up by 665,000 millionaire accounts (60.3% Gen X, average 25 years saving).
Fidelity\'s "10x by 67" rule
Fidelity recommends having approximately 10 times your annual salary saved for retirement by age 67. This benchmark assumes Social Security covers about 40% of pre-retirement income and your savings cover the rest. Their interim age-based benchmarks:
On an $85,000 salary, that means $85K saved by 30, $255K by 40, $510K by 50, $680K by 60, and $850K by 67. If you are behind, the fix is mathematical: increase your savings rate. Going from 8% to 12% of salary, sustained for 20 years, can roughly double your final balance compared to staying at 8%.
Three real 401(k) scenarios
1. The 25-year-old who started early
Sarah starts her career at age 25 earning $55,000. She contributes 10% to her 401(k) and gets a 4% employer match. Salary grows 2.5%/year, returns average 7% real. By age 67 (42 years later), her balance hits roughly $2.3 millionin today\'s dollars. Her own contributions over 42 years total about $290,000. The employer match adds another $115,000. The remaining $1.9 million is pure compound growth. Time in the market is the entire game.
2. The 45-year-old who started late
Mike has $25,000 saved at age 45 and earns $95,000. He needs to make up for lost time. Contributing the maximum $24,500/year (using catch-up at 50+) and getting a 4% match, he reaches about $890,000 by age 67. That is significantly less than Sarah despite contributing twice as much per year. The lesson: a single decade of compound growth in your 20s is worth more than two decades of aggressive saving in your 50s.
3. The high earner caught by Roth catch-up
Lisa is 52, earns $185,000, and has been making the maximum $32,500 contribution (regular $24,500 + catch-up $8,000) all pre-tax through 2025. Starting January 1, 2026, SECURE 2.0 requires her $8,000 catch-up to be Roth-only because she exceeds the $150,000 threshold. Her employer\'s plan does not offer a Roth 401(k) option yet, so until they add one, she can only contribute the regular $24,500 — losing $8,000 of annual contribution capacity. Plans nationwide are scrambling to add Roth options.
Common 401(k) mistakes
1. Not capturing the full employer match
If your employer matches 100% of the first 4% of contributions and you only contribute 2%, you are leaving 2% of your salary in free money on the table every single year. This is the highest-return investment available to most workers.
2. Picking expensive funds inside the 401(k)
A 1% expense ratio compounded over 30-40 years can cost you hundreds of thousands of dollars. Look for index funds with expense ratios under 0.10%. Most plans now offer them.
3. Cashing out when changing jobs
Every dollar you cash out before 59½ costs you income tax + 10% penalty + decades of compound growth. Roll it to an IRA instead.
4. Not increasing contributions with raises
Set up auto-escalation so your contribution rate goes up by 1% each year automatically. You will not feel it, and the long-term compounding is enormous.
5. Borrowing from your 401(k)
401(k) loans are tempting because the interest goes back to you. But you lose growth on the borrowed amount, you pay back with after-tax dollars, and if you leave your job the loan typically becomes due immediately or it is treated as a distribution.
Frequently asked questions
What is the 401(k) contribution limit for 2026?
The IRS announced that the 2026 401(k) employee contribution limit is $24,500, up from $23,500 in 2025. Workers age 50 and older can make additional catch-up contributions of $8,000, for a total of $32,500. Under SECURE 2.0, workers ages 60-63 get a higher "super catch-up" of $11,250, bringing their total to $35,750. The combined employee plus employer contribution limit for 2026 is $72,000 (or $80,000 for age 50+, $83,250 for ages 60-63).
What is the SECURE 2.0 Roth catch-up rule that starts in 2026?
Beginning January 1, 2026, workers age 50+ who earned more than $150,000 in FICA wages in the prior year are required to make their catch-up contributions on a Roth (after-tax) basis only. This rule applies to 401(k), 403(b), and 457 plans. If your plan does not offer a Roth 401(k) option, you cannot make catch-up contributions at all under the new rule. The IRS finalized these regulations on September 16, 2025, with general applicability for taxable years beginning after December 31, 2026.
How much should I contribute to my 401(k)?
Fidelity and most retirement experts recommend saving 15% of your gross income for retirement, including any employer match. The Fidelity 2025 data shows the average participant saves 9.5% themselves and gets an additional 4.7% from their employer match — totaling 14.2%, very close to the recommended target. At minimum, contribute enough to capture your full employer match. Beyond that, work toward 15% total. If you cannot hit 15% immediately, increase your contribution rate by 1% each year until you do.
What is the average employer 401(k) match in 2026?
According to Fidelity Q4 2025 data, 88.1% of plan participants receive an employer match, and the average match works out to 4.7% of salary. The most common match formula is 100% of the first 3% of employee contributions plus 50% of the next 2% — meaning if you contribute 5% of your salary, your employer adds 4% (3% from the first match + 1% from the half-match on the next 2%). On a $100,000 salary, that is $4,000 of free money per year that you only get if you actually contribute the full 5%.
What is the average 401(k) balance by age?
Per Fidelity Q4 2025 data (24.8 million accounts): Gen Z averages $17,900, Millennials average $83,700, Gen X averages $222,100, and Baby Boomers average $270,800. The all-ages average is $146,400, but the median (which is more representative of the typical saver) is just $34,400. About 665,000 Fidelity 401(k) accounts now have balances over $1 million — up from 537,000 the prior year. 60.3% of those millionaires are Gen Xers with an average tenure of 25 years saving.
How does the 401(k) employer match work?
An employer match is money your employer adds to your 401(k) based on what you contribute. The most common structure is "100% of the first 3% plus 50% of the next 2%" — meaning if you put in 5% of your paycheck, your employer adds 4%. Some employers use simpler structures like "100% of the first 6%" or "50% of the first 6%". Critically, you only get the match if you contribute enough to trigger it. Failing to contribute the full match-eligible amount is leaving free money on the table.
What is "Fidelity's 10x by 67" rule?
Fidelity recommends having approximately 10 times your annual salary saved for retirement by age 67. Their interim benchmarks are: 1x salary by 30, 3x by 40, 6x by 50, 8x by 60, and 10x by 67. So if you earn $80,000 at age 40, you should have around $240,000 saved. The benchmarks assume you will replace about 45% of your pre-retirement income from your 401(k)/IRA savings (with Social Security covering most of the rest), and live to about 92.
Should I contribute to a Roth 401(k) or a traditional 401(k)?
Traditional 401(k) gives you a tax break now (the money comes out of your paycheck pre-tax) but you pay income tax on withdrawals in retirement. Roth 401(k) is the reverse — no tax break now, but withdrawals in retirement are tax-free. Rule of thumb: if you expect to be in a lower tax bracket in retirement than today, choose traditional. If you expect to be in a higher bracket (or you are early in your career with low income), choose Roth. Many savers split contributions between both for tax diversification.
What happens to my 401(k) if I leave my job?
You have four options: (1) Leave it with your former employer (often allowed if balance is over $7,000). (2) Roll it over to an IRA at any brokerage like Fidelity, Schwab, or Vanguard — this is the most flexible option and often has lower fees. (3) Roll it into your new employer's 401(k) plan if they accept rollovers. (4) Cash it out — almost always the worst choice because you owe income tax plus a 10% early withdrawal penalty if under age 59½, and you lose decades of compound growth.
When can I withdraw from my 401(k) without penalty?
Generally at age 59½. Before that age, withdrawals are subject to ordinary income tax plus a 10% early withdrawal penalty. Exceptions include: separation from service in or after the year you turn 55 (the "Rule of 55"), substantially equal periodic payments (SEPP/72(t)), disability, certain medical expenses, qualified domestic relations orders, and birth or adoption of a child (up to $5,000). Required minimum distributions (RMDs) now begin at age 73 under SECURE 2.0, rising to age 75 in 2033.
How much will my 401(k) actually be worth at retirement?
It depends entirely on your contribution rate, employer match, time horizon, and investment returns. As a rough rule of thumb: contributing 15% of a $75,000 salary for 30 years at a 7% real return grows to about $1.1 million in today's dollars. Cut the time horizon in half (start at age 45 instead of 35) and you end up with about $300,000 — illustrating the brutal math of starting late. The calculator above projects your specific situation.
Why does the 7% expected return assumption matter?
A 7% real (inflation-adjusted) annual return is the standard long-term assumption for diversified stock-heavy retirement portfolios, based on historical S&P 500 averages of about 10% nominal minus roughly 3% inflation. The S&P 500 returned 16.39% in 2025, but you cannot count on any single year. Using 7% gives a conservative-realistic projection. Using 10% will overstate; using 4% understates. The calculator above defaults to 7% but you can adjust if you want to model a more or less optimistic scenario.
Data sources: IRS Notice 2025-67 (November 13, 2025) for 2026 contribution limits; Fidelity Investments Q4 2025 Retirement Analysis (24.8 million 401(k) accounts); Vanguard "How America Saves 2025" report; Treasury and IRS final regulations on SECURE 2.0 Roth catch-up rule (September 16, 2025); Fidelity benchmark "save 10x salary by 67" methodology.
Last updated: April 2026. Contribution limits change annually each November when the IRS releases COLA adjustments.
Disclaimer: This calculator provides estimates for educational purposes only and is not financial or tax advice. Projections assume constant return rates and do not account for sequence-of-returns risk. Consult a qualified financial advisor for personalized retirement planning.