Stop guessing your take-home pay. See how saving 10% for retirement only drops your paycheck by roughly 9.6% with our instant pre-tax simulator. No signup required.
When you contribute to a traditional 401(k), the IRS counts that money as if you never earned it — until you withdraw in retirement. Every pre-tax dollar you set aside today lowers the taxable income on which you pay federal and state income taxes right now.
A $200 contribution does not cost you $200 in take-home pay. If you are in the 22% federal bracket, the government was going to take $44 of that $200 anyway. Your real out-of-pocket cost is closer to $156. This simulator shows you the exact gap.
This tool is built for U.S. employees with a workplace 401(k) plan who want to understand the actual paycheck impact of contributing more. Use it to find a contribution rate where the drop feels manageable.
True Net Pay uses six steps:
Formula: Net Pay = Gross − 401(k) − Federal Tax − State Tax − FICA
Tax Shield = Tax owed without contribution − Tax owed with contribution.
Alex is single, earns $70,000/year, and contributes $6,000/year (8.6%) to his traditional 401(k).
Money taken from your paycheck before federal and most state income taxes are calculated, reducing your taxable income for the current year.
Pre-tax contributions lower your taxable income. The taxes you would have paid on that money stay in your pocket — that is your Tax Shield.
The amount of income tax you avoid each year because your 401(k) contributions are deducted from your paycheck before taxes are calculated.
Traditional contributions are pre-tax (lower your taxable income now; taxed on withdrawal). Roth contributions use after-tax dollars (no current tax break; qualified withdrawals in retirement are tax-free). This calculator models traditional pre-tax contributions only.
No — employer match dollars go directly into your account without reducing your paycheck. Only your personal contribution affects take-home pay.
Employee limit: $23,500. Age 50+ catch-up: $7,500 extra (total $31,000). Ages 60–63 special catch-up: $11,250 extra (total $34,750).
No. True Net Pay is for educational use only. Always consult a CPA or financial planner before making retirement decisions. See the Disclaimer.
No. All calculations run in your browser. Nothing you enter is sent to a server or saved.
True Net Pay provides estimated tax calculations for educational purposes only, using 2026 federal parameters. This is not financial or tax advice. © 2026 True Net Pay. About • Disclaimer • Privacy • Terms