401(k) paycheck calculator
Raise the contribution and watch the federal line fall while Social Security and Medicare stay exactly where they were. That is the part most calculators get wrong.
Where every dollar goes
2026 tax year · 26 pay periods| Line | Per paycheck | Per year |
|---|---|---|
| Gross pay | $2,615.38 | $68,000.00 |
| 401(k) contribution | −$130.77 | −$3,400.00 |
| Federal income tax | −$130.46 | −$3,392.00 |
| Social Security | −$162.15 | −$4,216.00 |
| Medicare | −$37.92 | −$986.00 |
| Texas state income tax | $0.00 | $0.00 |
| Take-home pay | $2,154.08 | $56,006.00 |
What each contribution rate actually costs you
On an $80,000 salary, single filer, Texas, paid every two weeks. The last column is the part that surprises people: what your take-home actually drops by, which is always less than you contributed.
| Contribution | Into your 401(k) | Take-home per paycheck | Federal tax saved | Real cost to take-home |
|---|---|---|---|---|
| 0% | $0 | $2,504.23 | $0 | $0 |
| 3% | $2,400 | $2,432.23 | $528 | $1,872 |
| 5% | $4,000 | $2,384.23 | $880 | $3,120 |
| 8% | $6,400 | $2,312.23 | $1,408 | $4,992 |
| 10% | $8,000 | $2,264.23 | $1,760 | $6,240 |
| 15% | $12,000 | $2,144.23 | $2,640 | $9,360 |
At 10% on this salary you put $8,000 away but your take-home falls by considerably less, because the contribution comes out before income tax is worked out. The difference is tax you would otherwise have paid.
What a contribution does not do is reduce Social Security or Medicare. Those are charged on pay before the deferral, so your FICA bill is identical at 0% and at 15%. This is the single most common misunderstanding about 401(k) contributions, and it is why the saving is smaller than your marginal rate suggests.
2026 contribution limits
The elective deferral limit for 2026 is $24,500. If you are 50 or over you can add a catch-up of $8,000, and between 60 and 63 the catch-up rises to $11,250.
These limits cover what you choose to defer. Employer matching sits on top and does not count against them. The combined limit including employer contributions is considerably higher.
One state does things differently. Pennsylvania counts 401(k), 403(b) and governmental 457(b) contributions as taxable compensation for state tax, even though the IRS does not. A Pennsylvania resident contributing 10% still pays Pennsylvania's 3.07% on the full salary. See the Pennsylvania paycheck calculator for what that costs.
Common questions
- How much does a 401(k) contribution reduce my paycheck?
- By less than you contribute. At a 22% marginal rate, $100 into a 401(k) reduces take-home by about $78, because the contribution lowers your taxable wages. Social Security and Medicare are unaffected.
- What is the 401(k) limit for 2026?
- The elective deferral limit is $24,500 for 2026, plus a $8,000 catch-up at 50 or over, and $11,250 between 60 and 63. Employer matching does not count towards it.
- Does a 401(k) reduce Social Security tax?
- No. Social Security and Medicare are charged on pay before any 401(k) deferral. Only income tax is reduced, which is why your W-2 shows a higher figure in box 3 than in box 1.
- Should I contribute enough to get the full match?
- An employer match is an immediate return on the contribution, and most financial guidance treats contributing at least to the full match as the baseline. This calculator shows what each rate costs your take-home so you can judge what is affordable.
Choose your state
State rules change the answer more than anything else on this page.