Gross salary to net paycheck: 2026 federal brackets, Social Security and Medicare, pre-tax benefits, and a flat state rate.
HSA and health premiums (cafeteria plan) skip income tax and FICA; 401(k) skips income tax only.
Set to 0 for no-income-tax states (TX, FL, WA, …). Real state brackets vary; this flat rate is an approximation.