401(k) Retirement Calculator — How Much Should You Save by Age?

A 30-year-old in Chicago earning $75,000 and contributing 6% of their salary to a 401(k) with a 3% employer match will retire with approximately $1.8 million at age 65 — assuming a 7% annual return. But bump that contribution to 10%, and the number jumps to $2.4 million. That's an extra $600,000 from just 4% more of your paycheck.

The gap between "comfortable retirement" and "barely scraping by" often comes down to a few percentage points decided decades earlier. A 401(k) retirement calculator turns abstract numbers into a concrete plan you can act on today.

How a 401(k) Actually Works (Quick Refresher)

A 401(k) is an employer-sponsored retirement plan that lets you contribute pre-tax dollars from your paycheck. The money grows tax-deferred until you withdraw it in retirement. Here's why it's the most powerful wealth-building tool available to American workers:

• Tax-deferred growth: You don't pay taxes on gains until withdrawal, which means more money compounds over time.
• Employer match: Most US employers match 50%–100% of your contributions up to 3%–6% of salary. This is free money — a guaranteed 50%–100% return on your contribution.
• 2026 contribution limits: The IRS allows $23,500 for employees under 50, and $31,000 for those 50 and older (catch-up contributions).
• Automatic investing: Contributions are deducted before you see your paycheck, which removes the friction of manual saving.

How Much Should You Have in Your 401(k) by Age?

Financial advisors use a common benchmark: save multiples of your annual salary by certain ages. Here's the widely-cited Fidelity guideline for someone earning around the US median household income ($74,580 in 2025):

“These are guidelines, not rules. A software engineer in San Francisco earning $200K needs more than someone in rural Kansas earning $50K. Use our calculator to get numbers specific to your situation.

The Employer Match: Free Money You Might Be Leaving on the Table

According to the Bureau of Labor Statistics, one in four US workers doesn't contribute enough to get their full employer match. If your employer matches 50% of your contributions up to 6% of salary, here's what that looks like on a $80,000 salary:

Contributing 3% instead of 6% costs you $340,000 over 30 years — and that's just from missing the match. The baseline rule: always contribute at least enough to get the full employer match.

Compound Growth: Why Starting Early Beats Saving More Later

The math of compound interest is brutally simple. Every year you wait to start contributing costs exponentially more later. Consider two workers who both retire at 65 with a 7% average return:

The late starter needs to contribute more than double ($1,050 vs $500) to achieve the same outcome — and they still invest $138,000 more out of pocket. Time in the market beats timing the market, every time.

Real-World Scenario: David and Rachel in Denver

David, 32, and Rachel, 29, are a dual-income couple in Denver, Colorado. David earns $95,000 as a project manager; Rachel earns $72,000 in marketing. Both have 401(k) plans with employer matching.

They used our 401(k) Retirement Calculator to model three scenarios:

1. 1Current plan (6% + match): Combined balance at 65: $2.1M. Comfortable but tight in a high-cost area.
2. 2Bumped to 10% + match: Combined balance at 65: $3.2M. Enough for a paid-off home plus $8,500/month in retirement income.
3. 3Maxed out ($23,500 each): Combined balance at 65: $5.4M. Early retirement at 58 becomes feasible.

The visualization helped them see that going from 6% to 10% added $1.1M to their retirement — for an extra $560/month today. They chose scenario 2 and set up automatic annual contribution increases of 1% until they hit the IRS maximum.

5 Smart 401(k) Strategies for 2026

1. 1Auto-escalate contributions: Most 401(k) plans let you automatically increase your contribution by 1% annually. You won't feel the difference in your paycheck, but it compounds massively.
2. 2Consider Roth 401(k): If you expect to be in a higher tax bracket in retirement, a Roth 401(k) lets you pay taxes now at your current rate. Use our 401(k) vs IRA Comparison Tool to see which makes more sense.
3. 3Rebalance annually: Your target-date fund handles this automatically, but if you're picking individual funds, rebalance once a year to maintain your desired stock-to-bond ratio.
4. 4Don't forget about old 401(k)s: If you've changed jobs, roll old employer plans into your current 401(k) or a traditional IRA. Orphaned accounts often sit in money market funds earning near-zero returns.
5. 5Max the catch-up contribution: Workers 50+ can contribute an extra $7,500 (2026 limits). If you're behind on savings, this is your most powerful accelerator.

Traditional vs Roth 401(k): Which Is Better?

If you're under 35 and expect your income to grow significantly, a Roth 401(k) often wins. You're paying taxes at today's lower rate to enjoy tax-free growth for 30+ years. Use our Roth IRA Calculator to compare potential tax savings.

Complete Your Retirement Planning (All Free)

A 401(k) calculation is one component of a full retirement strategy. Pair it with these tools for a comprehensive view:

• 401(k) Retirement Calculator: Project your balance with custom salary, contribution, match, and return assumptions.
• 401(k) vs IRA Comparison: Compare Traditional 401(k), Roth 401(k), Traditional IRA, and Roth IRA side by side.
• Roth IRA Calculator: Model tax-free retirement growth and see how Roth contributions compare to taxable accounts.