401k Calculator
Plan your retirement with our free 401k Calculator. Estimate your 401k balance at retirement, including employer matching, regular contributions, and the power of compound growth.
What Is a 401k?
A 401(k) is a tax-advantaged retirement savings plan offered by many employers in the United States. Named after the section of the IRS tax code that governs it, a 401(k) allows employees to contribute a portion of their pre-tax salary toward retirement investments. Many employers offer a matching contribution, where they contribute additional funds based on the employee's contributions — essentially free money toward your retirement.
The funds in a 401(k) grow tax-deferred, meaning you don't pay taxes on investment earnings until you withdraw them in retirement. This tax deferral, combined with compound growth and employer matching, makes the 401(k) one of the most powerful tools for building retirement wealth.
How Does the 401k Calculator Work?
Our 401k calculator projects your account balance at retirement using the following key inputs:
Projected Balance = (Starting Balance + Annual Contributions + Employer Match) × (1 + r/n)n repeated for each year until retirement
Where:
Annual Contributions = Salary × Contribution Rate
Employer Match = min(Annual Contributions × Match Rate, Salary × Match Cap)
r = Expected annual return (as a decimal)
n = Compounding frequency per year
The calculator runs year-by-year from your current age to your retirement age, applying:
- Employee contributions — a percentage of your salary each year.
- Employer match — based on your contribution and the match formula.
- Investment growth — compounded at your expected annual return rate.
- Inflation adjustment (optional) — to show your balance in today's purchasing power.
The result is a detailed projection of your 401k balance at retirement, along with a year-by-year breakdown and a growth chart to visualize your journey.
Why Use This 401k Calculator?
- Comprehensive: Includes employer matching, contribution increases, salary growth, and inflation.
- Free & Private: No registration, no data storage — your numbers stay on your device.
- Visual & Detailed: See your growth year-by-year with an interactive chart and breakdown table.
- Plan Smarter: Adjust inputs to see how changes in contributions, returns, or retirement age affect your future.
- Mobile-Friendly: Works on any device, from desktop to smartphone.
Which Factors Most Affect Your 401k Balance?
- Contribution Rate: Even a 1% increase can add tens of thousands over a career.
- Employer Match: Never leave free money on the table — contribute at least enough to get the full match.
- Investment Returns: A higher average return dramatically increases your final balance.
- Time Horizon: Starting early gives your money decades to compound — the most powerful factor of all.
- Salary Growth: As your income rises, your contributions (and match) grow too.
- Inflation: Erodes purchasing power — use the inflation adjustment to see your balance in real terms.
❓ 401k Frequently Asked Questions
What is a 401(k) and how does it work?
A 401(k) is an employer-sponsored retirement account where you contribute pre-tax income. Your contributions are invested in funds you choose, and the account grows tax-deferred until retirement. Many employers offer matching contributions, making it one of the most effective retirement savings vehicles.
What is the difference between a traditional 401(k) and a Roth 401(k)?
A traditional 401(k) uses pre-tax contributions, meaning you get a tax break now but pay taxes on withdrawals in retirement. A Roth 401(k) uses after-tax contributions, so you pay taxes now but enjoy tax-free withdrawals in retirement. Many employers now offer both options.
How does employer matching work in a 401(k)?
Employer matching means your employer contributes additional money to your 401(k) based on your contributions. A common formula is "50% of your contributions up to 6% of your salary" — if you contribute 6% of your salary, your employer adds another 3%. This is essentially free money for your retirement.
What are the 401(k) contribution limits for 2025?
For 2025, the employee contribution limit increases to $23,500 with the same $7,500 catch-up. Total contributions (employee + employer) cannot exceed $70,000 in 2025.
When can I withdraw from my 401(k) without penalty?
You can withdraw penalty-free starting at age 59½. Early withdrawals before that age incur a 10% penalty plus ordinary income tax, unless you qualify for exceptions such as hardship, disability, or certain medical expenses. Required Minimum Distributions (RMDs) must begin at age 73 (or 75 for those born after 1960).
What happens to my 401(k) if I change jobs?
When you leave a job, you have several options: leave the money in your old 401(k), roll it over to your new employer's plan, or transfer it to a traditional IRA. Rolling over to an IRA often gives you more investment choices and lower fees.
What is a vesting schedule in a 401(k)?
Vesting determines how much of your employer's matching contributions you actually own. With a graded vesting schedule, you gain ownership gradually over 3-6 years. With cliff vesting, you become fully vested after a set number of years. Your own contributions are always 100% vested.
How are 401(k) withdrawals taxed?
Withdrawals from a traditional 401(k) are taxed as ordinary income at your marginal tax rate in the year you withdraw. Roth 401(k) withdrawals are tax-free if you're 59½ and have held the account for at least 5 years. Withdrawals before 59½ generally incur a 10% penalty in addition to income tax.
What is a target-date fund and should I use one in my 401(k)?
A target-date fund automatically adjusts its investment mix as you approach retirement — more aggressive when you're young, more conservative as retirement nears. It's a "set it and forget it" option that can be a great choice for hands-off investors, though fees can be higher than building your own portfolio.
Can I have both a 401(k) and an IRA?
Yes. You can contribute to both a 401(k) and an IRA in the same year, as long as you meet income limits for IRA deductions. Many people max out their 401(k) match first, then contribute to an IRA for additional tax-advantaged savings and more investment choices.
What is a catch-up contribution for a 401(k)?
Catch-up contributions allow individuals aged 50 and older to contribute extra funds beyond the standard limit. For 2024, the catch-up limit is $7,500, bringing the total to $30,500. For 2025, the catch-up remains $7,500, with a total limit of $31,000.
How does a 401(k) loan work?
Some plans allow you to borrow from your 401(k) — typically up to 50% of your vested balance or $50,000, whichever is less. You must repay the loan with interest over a set period (usually 5 years). If you leave your job, the outstanding balance may become due immediately, or it's treated as a taxable distribution with penalties.
What investment options are typically available in a 401(k)?
Most 401(k) plans offer a mix of mutual funds, including stock funds, bond funds, target-date funds, and sometimes company stock. The specific options depend on your plan provider. Look for funds with low expense ratios to keep more of your returns.
How does inflation affect my 401(k) savings?
Inflation erodes the purchasing power of your retirement savings. A 3% inflation rate means $1,000 today will only buy what $744 can buy in 10 years. Our calculator includes an inflation adjustment option so you can see your projected balance in today's dollars — a more realistic picture of your retirement buying power.
What is the difference between a 401(k) and a pension?
A 401(k) is a defined-contribution plan — you and your employer contribute, and your retirement balance depends on investment performance. A pension is a defined-benefit plan — your employer promises you a specific monthly payment in retirement based on your salary and years of service. Pensions are becoming rare in the private sector.
How often should I review and rebalance my 401(k)?
Financial experts recommend reviewing your 401(k) at least once a year — and after major life events like a job change, marriage, or nearing retirement. Rebalancing annually helps maintain your desired asset allocation and risk level. Many target-date funds handle this automatically.
Is a 401(k) worth it if my employer doesn't offer a match?
Absolutely. Even without a match, a 401(k) offers significant tax advantages: tax-deferred growth and the ability to lower your taxable income today. The tax benefits alone can boost your long-term returns substantially compared to a taxable brokerage account.