Salary After Tax Calculator 2026 Methodology (IRS, SSA, and State Sources)

Methodology, sources, and limitations

Tax year signal: the calculator defaults to Tax Year 2026. Federal ordinary-income brackets and standard deductions come from Utilnivo’s payroll dataset (src/data/payroll/2026/federal.ts), aligned to IRS inflation-adjusted amounts for the year.

FICA: employee Social Security uses the 2026 wage base and rate from src/data/payroll/2026/fica.ts (SSA contribution and benefit base). Medicare and Additional Medicare follow published employee rates and liability thresholds by filing status.

State income tax: for bundled detailed states (CA, NY, PA, IL, OH, GA, NC, NJ, VA, MA) the annual engine applies progressive or flat tables from src/data/payroll/states/detailed/*-2026.json. No-income-tax states (for example TX, FL, WA) return $0 state wage income tax. Remaining states use a labeled simplified effective rate—not a claim of full DOR withholding accuracy.

Deductions modeled: optional traditional 401(k), HSA, and health premiums reduce taxable wages as documented in the calculator accuracy panel. Child tax credit and most other credits are not modeled.

Intent mapping: use Salary After Tax for annual take-home / salary-after-tax queries; Paycheck Calculator for one pay period; Salary Calculator for gross conversion; Hourly to Salary for hourly↔annual.

Limitations: this is an educational annual liability estimate, not Pub. 15-T paycheck withholding, not a substitute for tax filing software, and not advice. Verify critical decisions against your pay stub, employer payroll, and official IRS/SSA/state revenue sources.