401(k) Contribution & Growth Calculator

Why a 401(k) costs less than it saves

Traditional 401(k) contributions are deducted from your salary before federal and state income tax. So if you're in the 22% federal bracket and contribute $1,000, your take-home pay only falls by about $780 — the rest would have been paid in tax anyway. On top of that, many employers match a portion of what you put in, which is an immediate, guaranteed return.

Take-home impact = contribution − income tax saved

401(k) contribution calculator FAQ

How does a 401(k) affect my take-home pay?

Traditional 401(k) contributions come out of your paycheck before federal and state income tax, so your take-home pay drops by less than the amount you contribute. For example, contributing $300 might only reduce your paycheck by about $220 because the other $80 would have gone to taxes.

How much should I contribute to my 401(k)?

A common starting point is to contribute at least enough to get your full employer match — that's free money. Many advisors suggest working toward 10–15% of your salary over time. Use the slider above to see how each percentage changes your paycheck and tax bill.

What is the 401(k) contribution limit for 2024?

The 2024 employee contribution limit is $23,000. If you're 50 or older, you can add a $7,500 catch-up contribution for a total of $30,500. Employer matching contributions are on top of these limits.

Does a 401(k) reduce Social Security and Medicare taxes?

No. Traditional 401(k) contributions lower your federal and state income tax, but Social Security and Medicare (FICA) taxes are still charged on your full gross wages.

How much will my 401(k) be worth at retirement?

It depends on how much you contribute, your employer match, your years until retirement and your average annual return. The growth projection above compounds your yearly contributions plus match at the return you enter. As a rough example, $7,500 a year (you plus match) at a 7% return for 30 years grows to roughly $760,000 — most of it from compounding, not contributions.

How do I calculate my 401(k) contribution on each paycheck?

Multiply your gross pay for the period by your contribution percentage. For example, 6% of a $2,500 biweekly paycheck is $150. Because traditional contributions are pre-tax, your take-home only drops by about $150 minus the income tax you would have paid on it. The calculator above does this for you and also shows the monthly figure.