Introduction
A 401(k) is one of the best ways to save money for retirement. It lets you put part of your paycheck into an account that grows over time. Many employers even match some of what you put in, which is like getting free money. But figuring out how much your 401(k) will be worth when you retire can be tricky. That's where this 401(k) calculator comes in.
This tool helps you see how much money you could have saved by the time you stop working. Just enter a few details like your age, how much you earn, how much you plan to save each year, and any employer match you get. The calculator does the math for you and shows you how your savings can grow over time. Use it to plan ahead and make smart choices about your retirement savings.
How to Use Our 401k Calculator
Enter your income, savings, and retirement details below to see how much your 401k could grow by the time you retire.
Current Age: Enter how old you are right now. This helps the calculator figure out how many years you have left to save before retirement.
Retirement Age: Enter the age you plan to stop working. Most people choose somewhere between 59½ and 67, but you can pick any age that fits your plan.
Annual Salary: Enter the total amount of money you earn each year before taxes. Your 401k contributions are based on this number. If you need help converting your pay to an annual figure, try our hourly to salary calculator or salary to hourly calculator.
Contribution Percentage: Enter the percentage of your paycheck you put into your 401k each pay period. For example, if you save 10% of your salary, type in 10.
Employer Match Percentage: Enter the percentage your employer adds to your 401k on top of what you contribute. For instance, if your company matches 50% of your contributions, type in 50.
Employer Match Limit: Enter the maximum percentage of your salary that your employer will match. Many companies only match up to a certain percent, such as 6%.
Current 401k Balance: Enter the total amount of money you already have saved in your 401k account right now.
Expected Annual Rate of Return: Enter the yearly percentage you expect your investments to grow. A common estimate is between 6% and 8%, but this can vary based on how your money is invested. You can use the Rule of 72 calculator to quickly estimate how long it takes your money to double at a given return rate.
Annual Salary Increase: Enter the percentage raise you expect to get each year. This helps the calculator account for higher contributions as your pay grows over time.
A 401(k) is a retirement savings plan offered by many employers in the United States. It lets you set aside a portion of your paycheck before taxes are taken out, which lowers your taxable income for the year. The money you contribute gets invested in options like stocks, bonds, and mutual funds, and it grows tax-deferred until you withdraw it in retirement.
How 401(k) Contributions Work
Each pay period, a percentage of your gross salary goes directly into your 401(k) account. For 2025, the IRS allows you to contribute up to $23,500 per year if you're under 50, or $31,000 if you're 50 or older. These limits are called catch-up contributions, and they help older workers save more as retirement gets closer. Because contributions are made with pre-tax dollars in a traditional 401(k), you don't pay income tax on that money until you withdraw it later. To understand how much of your paycheck actually ends up in your pocket after contributions and taxes, check out our take home pay calculator.
Employer Matching: Free Money for Your Retirement
One of the biggest benefits of a 401(k) is the employer match. Many companies will add extra money to your account based on how much you contribute. A common example is a 50% match on the first 6% of your salary. That means if you earn $75,000 and contribute 6% ($4,500), your employer adds another $2,250. If you don't contribute enough to get the full match, you are leaving free money on the table. Always try to contribute at least enough to get every dollar your employer is willing to give you.
The Power of Compound Growth
The real strength of a 401(k) comes from compound interest. When your investments earn returns, those returns get reinvested and start earning their own returns. Over 30 or 35 years, this snowball effect can turn modest monthly contributions into a very large nest egg. Our compound interest calculator can help you visualize exactly how this growth works with different contribution amounts and time horizons. Starting early matters a lot. Someone who begins saving at age 25 will typically end up with far more money than someone who starts at 35, even if they contribute the same amount, simply because their money has more time to grow. If you're exploring the idea of retiring earlier than the traditional age, our Coast FIRE calculator can show you at what point your existing savings may be enough to grow on their own without additional contributions.
Early Withdrawal Penalties
A 401(k) is designed for retirement, so the IRS discourages you from taking money out early. If you withdraw funds before age 59½, you will generally face a 10% early withdrawal penalty on top of regular federal and state income taxes. For example, pulling out $50,000 at age 35 could cost you $18,500 or more in penalties and taxes, leaving you with only about $31,500. Beyond the immediate hit, you also lose all the future growth that money would have earned. That same $50,000, left invested at a 7% average return for 30 years, could have grown to over $380,000. Use our future value calculator to see exactly how much a lump sum can grow over any time period.
The 4% Rule for Retirement Income
Financial planners often use the 4% rule as a guideline for how much you can safely withdraw each year in retirement without running out of money. It suggests you can take out 4% of your total savings in your first year of retirement, then adjust that amount for inflation each year after. So if you retire with $1,000,000, you could withdraw about $40,000 per year, or roughly $3,333 per month. Keep in mind that inflation erodes purchasing power over time, so what feels like enough today may not stretch as far in 20 or 30 years. This rule isn't perfect for everyone, but it gives a useful starting point for estimating how much you need to save. To track your full financial picture alongside your 401(k), you may want to use our net worth calculator.
Tips to Make the Most of Your 401(k)
- Start as early as possible. Even small contributions in your 20s can grow significantly by retirement.
- Always get the full employer match. It's an instant return on your money that you can't get anywhere else. Use our ROI calculator to appreciate the effective return an employer match provides.
- Increase your contribution rate over time. When you get a raise, put at least part of it toward your 401(k).
- Avoid early withdrawals. The penalties, taxes, and lost growth make this one of the most expensive financial decisions you can make.
- Review your investments yearly. Make sure your fund choices match your age and risk tolerance.
- Pay down high-interest debt. If credit card balances are holding you back from contributing more, our credit card payoff calculator or debt snowball calculator can help you create a payoff plan so you can redirect those payments into your 401(k).
- Consider other investments alongside your 401(k). A dividend calculator or DCA calculator can help you evaluate strategies for additional savings outside your employer plan.