How this calculator works
Start with gross wages for one pay period. Qualifying pre-tax deductions reduce the relevant taxable wages. The calculator then subtracts estimated taxes, post-tax deductions and any local amounts you enter. It calculates net from gross; it does not solve backwards for a desired net paycheck.
Example calculation
A $2,000 biweekly gross paycheck with $100 in traditional retirement contributions leaves $1,900 subject to federal income-tax withholding. Social Security and Medicare still apply to the full $2,000. With the default Single W-4 and Florida setting, net pay is approximately $1,602.85.
2026 methodology & assumptions
For regular U.S. employee wages with a 2020-or-later W-4. This estimate uses 52 weekly, 26 biweekly, 24 semi-monthly or 12 monthly pay periods. Federal withholding follows IRS Publication 15-T Worksheet 1A. Amounts are rounded to cents.
Social Security uses a $184,500 wage limit and 6.2% employee rate; Medicare uses 1.45%. Additional Medicare withholding is 0.9% on wages above $200,000 paid by the same employer, regardless of filing status. Enter year-to-date taxable wages before this paycheck to model those thresholds.
California uses EDD Method B annualization, including DE 4 allowances and 1.3% uncapped SDI. Period-specific tables may differ slightly because of rounding. Supplemental wages, nonresident-alien adjustments, self-employment tax, local taxes, special exemptions, and multi-state allocation are not automatically modeled. Overtime is not automatically treated as tax-free.
Frequently asked questions
Why is my retirement contribution still subject to FICA?
Traditional employee retirement deferrals generally reduce income-tax wages without reducing Social Security or Medicare wages. Qualifying cafeteria-plan benefits can have a different treatment.
Where do I enter garnishments or after-tax insurance?
Use post-tax deductions for amounts that reduce net pay without reducing taxable wages. Verify the tax treatment of each deduction with the plan or payroll administrator.
Sources & further reading
- IRS Publication 15-T (2026)
- IRS Social Security and Medicare withholding rates
- California EDD 2026 Method B tables (PDF)
- California SDI rates
- Florida Department of Revenue: personal income tax
- PayStubPro pay stub guide
Tax configuration reviewed September 19, 2026. Applicable tax year: 2026.