Methodology
Our calculator turns your gross annual income into an estimated net paycheck. This page explains the assumptions and formulas behind every result.
1. Federal income tax
We start with your gross annual income, subtract the 2026 federal standard deduction for your filing status, and apply the official IRS tax brackets using marginal tax rates.
- Single standard deduction: $16,100
- Married filing jointly: $32,200
- Married filing separately: $16,100
- Head of household: $24,150
2. FICA payroll taxes
We calculate Social Security and Medicare taxes as follows:
- Social Security: 6.2% on wages up to the 2026 wage base of $184,500.
- Medicare: 1.45% on all wages with no cap.
- Additional Medicare Tax: 0.9% on wages above $200,000 (single/HOH), $250,000 (joint), or $125,000 (separate).
3. State income tax
Each state is modeled as one of three types: no income tax, flat income tax, or progressive income tax. For progressive states, we subtract the state standard deduction and apply the state's marginal brackets.
4. Net pay
Net annual pay equals gross income minus federal income tax, FICA, and state income tax. We also show monthly and biweekly equivalents by dividing by 12 and 26.
5. Compare and embed tools
The state comparison tool runs the same engine for two states at once so you can evaluate a relocation or job offer. The embeddable calculator lets third-party sites add the calculator through a simple iframe.
Important assumptions
- We use the standard deduction only. Itemized deductions are not included.
- We do not model 401(k), HSA, FSA, or other pre-tax contributions.
- State taxable income is approximated as federal taxable income minus the state standard deduction or exemption.
- Local income taxes (for example, NYC, Yonkers, Ohio/PA localities) are not included yet.
- Where a state does not publish separate married-filing-separately or head-of-household brackets, we fall back to the single-filer schedule as a conservative estimate.
- All figures are estimates for the 2026 tax year.
Data sources
- IRS 2026 inflation adjustments
- Social Security 2026 wage base
- IRS Topic 751 (FICA)
- LevyIO 2026 State Income Tax Dataset
- Individual state revenue departments and the Tax Foundation for 2026 rate updates.