How this is calculated
net = salary − federal tax(salary − standard deduction) − 6.2% Social Security (capped) − 1.45% Medicare − state rate × taxable
The model walks your salary through the big four deductions. First the federal income tax: your salary minus the standard deduction ($15,000 for single filers, 2025) flows through progressive brackets from 10% to 37% — only the dollars inside each bracket pay that bracket's rate. Then FICA: 6.2% Social Security (up to the annual wage cap) and 1.45% Medicare on everything. Finally your state's income tax, which you set as a flat rate.
This is deliberately a simplified, single-filer model. Real paychecks also involve 401(k) contributions (which reduce taxable income), health insurance premiums, credits, married filing statuses, local taxes in some cities, and states with progressive brackets of their own. Each of those can move the result by real money.
Still, the estimate lands close enough to answer the questions people actually have — can I afford this rent, what does that job offer mean monthly, why is my paycheck smaller than salary ÷ 12. For filing taxes or financial planning, use official calculators or a professional.
Frequently asked questions
Why is my real paycheck different from this estimate?
Most often: 401(k) and health insurance premiums come out pre-tax (making net lower but taxes also lower), your filing status differs, or your state has progressive brackets rather than the flat rate you entered.
What is FICA?
The payroll taxes funding Social Security (6.2%, on wages up to a yearly cap) and Medicare (1.45%, uncapped; +0.9% above $200K). Your employer pays a matching share you never see.
Which states have no income tax?
Alaska, Florida, Nevada, New Hampshire, South Dakota, Tennessee, Texas, Washington and Wyoming currently levy no broad wage income tax — enter 0% for those.
Does this work for married filers?
Not accurately — brackets and the standard deduction differ for married filing jointly. Treat the single-filer result as a rough upper bound on your tax.