401k Calculator: Your Retirement Projection Tool
The most comprehensive free 401(k) calculator for US workers. Basic growth, advanced inflation modeling, catch-up contributions, tax savings, and withdrawal income — all in one place.
401(k) Retirement Calculator — 2026
5 Modes: Basic · Advanced · Catch-Up · Tax Savings · Withdrawal Income
| Year | Age | Salary | You | Employer | Bal. Start | Bal. End |
|---|
What Is a 401(k) Calculator and Why Every Worker Needs One
A 401(k) calculator turns abstract retirement planning into concrete, actionable numbers. It takes what you know today — your age, salary, current balance, contribution rate, and employer match — and projects forward to show you exactly what your account will be worth at retirement, assuming a given annual return.
Most Americans participate in a 401(k) plan but have little clarity on whether their contributions are sufficient. They see a quarterly balance, but they have no benchmark for what that number means in the context of their retirement income goals. This calculator closes that gap across five distinct modes — each designed to answer a different retirement planning question.
All Five Calculator Modes — What Each One Answers
Basic Mode — Core Growth Projection
Enter your age, salary, balance, contribution rate, employer match, and expected return. The calculator enforces 2026 IRS limits automatically and returns your projected balance, monthly retirement income estimate, and a full year-by-year growth table. This is the starting point for every participant.
Advanced Mode — Full Precision Planning
Adds salary growth modeling, inflation adjustment (showing real value in today’s dollars), fund expense ratio drag, state income tax, and federal tax bracket analysis. Essential for workers who want to understand the true net trajectory of their savings after all costs.
Catch-Up Mode — Ages 50+ Optimization
Models the SECURE 2.0 catch-up contribution provisions — $7,500 extra for ages 50–59 and 64+, and the new $11,250 super catch-up for ages 60–63. Shows the dollar bonus from maximizing catch-up contributions versus contributing at base limits only. One of the most powerful features for late-career savers.
Tax Savings Mode — See Your IRS Benefit
Calculates exactly how much federal and state income tax you save by making pre-tax 401(k) contributions. Uses 2026 tax brackets, your filing status, and standard deduction. Also shows the 30-year future value of those annual tax savings if reinvested at 7%.
Withdrawal Mode — Retirement Income Planning
Given a projected or actual balance at retirement, calculates sustainable annual and monthly income under four strategies: 4% Rule, 3% Conservative, 5% Aggressive, IRS RMD (with real RMD factors), or a custom fixed monthly amount. Includes Social Security and other income, and simulates whether the portfolio survives your expected lifespan.
2026 IRS 401(k) Contribution Limits
The IRS updates 401(k) contribution limits annually for inflation. For 2026, the limits reflect SECURE 2.0 Act provisions including the new super catch-up window for workers aged 60–63.
| Category | 2026 Limit | Notes |
|---|---|---|
| Employee Base Contribution (Under 50) | $23,500 | Traditional + Roth 401(k) combined |
| Standard Catch-Up (Age 50–59 & 64+) | $31,000 | +$7,500 above base limit |
| Super Catch-Up (Age 60–63) — SECURE 2.0 | $34,750 | +$11,250 above base — 4-year window only |
| Combined Employee + Employer Total | $70,000 | All contributions from all sources |
| IRA Contribution Limit (separate) | $7,000 / $8,000 (50+) | Independent of 401(k) limits |
The $23,500 limit applies only to your employee elective deferrals. Your employer’s matching contributions sit on top of this limit — they do not reduce your personal allowance. The $70,000 combined cap is the ceiling for everything together.
Employer Match: The Highest Guaranteed Return in Personal Finance
Before any investment strategy discussion, one fact overrides all others: the employer match is the highest guaranteed return available to American workers. A 50% match on your contributions is a 50% guaranteed return before your investment earns a single dollar in the market.
A worker earning $80,000 who contributes 6% of salary receives $4,800 contributed by themselves and $2,400 from their employer. That $2,400 at 7% annual growth over 25 years becomes approximately $13,000 — per year of the match. Over a full career, the employer match alone can add $200,000–$400,000 to your retirement balance. Missing it — by contributing below the match threshold — is the most expensive retirement mistake most workers make.
Vesting schedules matter: Some employers apply a vesting schedule — you must stay employed for a certain period before you own the employer match fully. Cliff vesting gives you 0% until a set date (often 3 years), then 100%. Graded vesting increases your ownership gradually. Leaving before full vesting forfeits unvested match dollars permanently.
Compound Interest and the One Variable That Matters Most
Of all the inputs in a 401(k) calculator — contribution rate, return rate, employer match — the single variable with the greatest impact is time. Compound interest is exponential. The earlier you start, the more of your final balance comes from growth rather than your own contributions.
| Start Age | Monthly Contribution | Total Contributed | Balance at 65 (7%) | Growth % |
|---|---|---|---|---|
| 25 | $500 | $240,000 | $1,310,000 | 81% |
| 30 | $500 | $210,000 | $913,000 | 77% |
| 35 | $500 | $180,000 | $624,000 | 71% |
| 40 | $500 | $150,000 | $415,000 | 64% |
| 50 | $600 | $108,000 | $181,000 | 40% |
Starting at 25 versus 35 produces $686,000 in additional wealth from just 10 extra years of contributions — even though you only contributed $60,000 more. The remaining $626,000 comes purely from compounding those early contributions for an extra decade. No investment strategy produces a $626,000 gain from $60,000 in extra contributions — only time does.
Six Strategies to Maximize Your 401(k) in 2026
1. Always Capture the Full Employer Match First
No other financial move has a guaranteed comparable return. Contribute at minimum to the employer match threshold before directing funds anywhere else — emergency fund expansions, Roth IRA, debt payoff. Only high-interest debt above 15–18% competes with the match math.
2. Increase Contributions by 1% With Every Raise
A 1% increase is rarely noticed in take-home pay — especially if implemented simultaneously with a raise. But 1% of a $75,000 salary is $750 per year, which at 7% over 30 years grows to $70,000 in additional wealth. Enabling auto-escalation in your plan makes this automatic.
3. Choose the Lowest-Cost Index Funds Available
A 0.80% expense ratio versus 0.05% on a $300,000 account costs approximately $2,250 per year in foregone growth. Over 20 years, that compounds to over $100,000 in lost wealth from fees alone. Total market and S&P 500 index funds with expense ratios below 0.10% are widely available in most 401(k) plan menus.
4. Maximize Catch-Up the Moment You Turn 50
The catch-up contribution window opens on your 50th birthday. Workers aged 60–63 have a four-year super catch-up window under SECURE 2.0 that allows $34,750 in annual contributions. These are the highest-income years for most workers — also the ideal time to maximize pre-tax sheltering. Model this in the Catch-Up tab above.
5. Rebalance Annually — Not Monthly
Markets move your asset allocation away from your target over time. Annual rebalancing — selling overweight positions and buying underweight ones — maintains your risk profile without excessive transaction activity. More frequent rebalancing adds friction without proportional benefit.
6. Use the Tax Savings Calculator Before Making Contribution Decisions
Many workers underestimate how much their 401(k) contributions cost them in actual take-home pay reduction. At a 22% marginal rate, a $10,000 contribution only costs $7,800 in actual take-home pay — the IRS subsidizes $2,200 through reduced withholding. The Tax Savings tab above makes this calculation concrete for any salary and contribution amount.
- Capture full employer match first — this is always priority one
- Base limit: $23,500 · Age 50+: $31,000 · Ages 60–63: $34,750
- Employer match contributions do not count against your personal limit
- Choose index funds with expense ratios below 0.20% to protect long-term growth
- Auto-escalate contributions by 1% each year — small steps compound significantly
- Use the Tax Savings tab to see your true after-tax cost of contributing
Traditional vs. Roth 401(k): Which Is Right for You?
Many employers now offer both options within the same plan. The choice reduces to one question: will your tax rate be higher now or in retirement?
| Feature | Traditional 401(k) | Roth 401(k) |
|---|---|---|
| Contribution tax treatment | Pre-tax — reduces income now | After-tax — no current deduction |
| Withdrawal tax treatment | Fully taxable as ordinary income | 100% tax-free (qualified withdrawals) |
| Required Minimum Distributions | Required at age 73 | Required in plan; roll to Roth IRA to avoid |
| Best for | High earners expecting lower retirement tax rate | Workers expecting higher future tax rates |
| 2026 contribution limit | $23,500 (under 50) | Same — limits are shared between both |
| Income limit | None | None (Roth 401k has no income limit) |