Transparency
How the calculator works
Kept is an annual tax-liability model for tax year 2026, not a payroll withholding engine. That distinction matters, and it is why a paycheck stub can disagree with these numbers.
Federal income tax
Ordinary rates and the standard deduction follow IRS Revenue Procedure 2025-32. Single filers get a $16,100 standard deduction; joint filers $32,200; heads of household $24,150. Brackets are applied to taxable income after that deduction, traditional 401(k) deferrals, and (for 1099) half of self-employment tax plus a simplified QBI deduction.
FICA and self-employment tax
Employees pay 6.2% Social Security up to a $184,500 wage base and 1.45% Medicare on all wages, plus 0.9% Additional Medicare Tax above $200,000 single / $250,000 joint. Contractors pay both halves on 92.35% of net profit. The employer match is not added to W-2 gross — it is an employer cost, not a stub line.
State and local tax
State brackets, flat rates, and standard deductions are compiled from 2026 published tables. Credits, recapture, AMT, and most city taxes are omitted unless you pick a city with a modeled local rate (New York City, Philadelphia, several Ohio and Maryland cities). Alabama's federal-tax deduction is not modeled. Treat state tax as a planning estimate.
Cost of living
City index values are Kept's 2026 planning set (US average = 100), combining housing and everyday prices. They are not BLS CPI. Rent figures are typical one-bedroom asking rents, rounded. Use them to compare cities, not to underwrite a lease.
What we skip on purpose
Child tax credit, EITC, SALT cap itemizing, property tax, sales tax, pre-tax health premiums beyond the 401(k) field, bonus supplemental withholding, and multi-state reciprocity. Adding them without a full return would pretend precision we do not have.