Introduction
Putting money in your 401(k) costs less than you think. This 401(k) contribution calculator shows how much your paycheck actually shrinks when you save for retirement, and that drop is usually smaller than the amount you put away.
Here is why. With a traditional 401(k), your money comes out before taxes. So you pay less federal and state income tax on that paycheck. Put in $200 and your take-home pay may only drop by about $150. The rest is money you would have handed to the IRS anyway.
Just type in your salary, your age, how often you get paid, and how much you want to save. The calculator shows your real cost per paycheck, your tax savings, your free employer match, and how close you are to the 2026 IRS limit of $24,500 (plus catch-up if you are 50 or older). You can switch between Traditional and Roth to see both side by side, and view the numbers per paycheck or per year.
You also get a full before-and-after paycheck breakdown, a chart of where every dollar goes, and step-by-step math so you can see how each number was found. Use it to find the contribution rate that grows your retirement savings without hurting your budget.
How to use our 401(k) Contribution Calculator
Enter your pay, your age, how much you want to put in your 401(k), your employer match, and your tax rates. The calculator shows your contribution per paycheck, your real take-home pay drop, your tax savings, free employer match money, and how close you are to the 2026 IRS limit.
Annual Gross Salary: Type your pay for the year before taxes or any deductions come out.
Current Age: Enter your age. This sets your IRS limit, since people 50 and up can add catch-up money, and ages 60 to 63 get a bigger super catch-up.
Pay Frequency: Pick how often you get paid: weekly, bi-weekly, semi-monthly, or monthly. Every per-paycheck number uses this.
Tax Filing Status: Choose single, married filing jointly, married filing separately, or head of household. This fills in your federal tax rate for you.
Account Type: Pick Traditional for pre-tax money that lowers your taxes now, or Roth for after-tax money that comes out tax-free later.
Contribution Input Mode: Choose to enter your 401(k) contribution as a percent of salary or as dollars per paycheck. The calculator shows the other one for you.
Contribution Percentage or Per Paycheck Amount: Type how much you want to save. If it goes over the IRS yearly limit, the results use the limit instead.
Employer Match Rate: Enter how much your employer adds per dollar you put in. 100% means dollar for dollar; 50% means fifty cents per dollar.
Match Cap (% of Salary): Enter the top percent of your pay your employer will match, like 3% or 6%.
Federal Income Tax Rate: We fill this with your tax bracket. You can change it to your effective rate for a closer take-home number.
State Income Tax Rate: Type your state rate. Use 0% if your state has no income tax.
Include FICA: Leave this on to count Social Security and Medicare taxes in your paycheck math. These taxes do not drop when you contribute to a 401(k).
Calculate and Reset: Results update as you type, but you can press Calculate any time. Press Reset to start over with the default numbers.
What a 401(k) Contribution Really Costs You
A 401(k) is a retirement account you get through your job. Money comes out of each paycheck and goes into the account, where it can grow for years. With a traditional 401(k), the money comes out before income tax, so your taxable pay drops. With a Roth 401(k), the money comes out after tax, but your qualified withdrawals in retirement are tax-free.
Why Your Paycheck Drops Less Than You Think
This is the part most people miss. If you put $200 into a traditional 401(k), your take-home pay does not fall by $200. Because that $200 is not taxed today, you also pay less federal and state income tax. If your combined rate is 27%, you save about $54 in taxes, so your paycheck only shrinks by about $146. You saved $200 for retirement and it cost you $146.
Roth works differently. Since Roth money is taxed first, your paycheck falls by the full amount. The payoff comes later, when you pull the money out tax-free.
One thing to know: 401(k) money still pays FICA tax (Social Security and Medicare). Those taxes come out of your full gross pay no matter which type you pick.
Employer Match Is Free Money
Many jobs add money to your 401(k) when you contribute. A common deal is "100% up to 3%." That means if you put in 3% of your salary, your employer puts in 3% too. On a $75,000 salary, that is $2,250 a year you did not have to earn.
If you contribute less than the match cap, you leave part of that money on the table. Getting the full match is usually the first goal, before anything else. Check your plan for a vesting schedule, since some employers require you to stay a few years before the match is fully yours.
2026 IRS Contribution Limits
The IRS caps how much you can put in each year from your own pay. Employer match does not count against these limits.
| Your Age in 2026 | Max Employee Contribution |
|---|---|
| Under 50 | $24,500 |
| 50 to 59 | $32,500 ($24,500 + $8,000 catch-up) |
| 60 to 63 | $35,750 ($24,500 + $11,250 super catch-up) |
| 64 and older | $32,500 ($24,500 + $8,000 catch-up) |
The bigger "super catch-up" for ages 60 to 63 comes from the SECURE 2.0 law. It is a short window, so it is worth using if you can.
Picking a Contribution Rate
- Start at the match cap. Never skip free employer money.
- Aim for 10% to 15% of pay over time, counting the match, for a solid retirement.
- Raise it 1% a year. Small jumps are easy to absorb, and many plans can do it automatically.
- Use raises. Bump your rate when your pay goes up and you will barely feel it.
Traditional or Roth?
A simple rule: pick traditional if you think your tax rate is higher now than it will be in retirement. Pick Roth if you think your tax rate will be higher later, which is often true for younger workers early in their careers. Splitting between both is also fine and gives you tax flexibility down the road.
These numbers are estimates. They use flat tax rates and do not include every deduction, credit, or local tax. Talk to a tax pro or financial advisor for advice on your own situation.