Mission and independence
The site pairs calculators with calm, practical explanations. It is an independent project. It is not the IRS, the Social Security Administration, or any state agency, and it is not your payroll provider.
The guides are sourced editorial guidance, not personalized legal or tax advice. For year-wide planning use the IRS Tax Withholding Estimator. For the amounts actually withheld, check your paystub or ask your payroll department.
What the default calculator models
- Regular resident wages, using a 2020-or-later federal Form W-4 and the W-4 election inputs you enter.
- 2026 source tables for paycheck withholding, kept separate from your annual return liability.
- Social Security at 6.2% up to the $184,500 wage base; Medicare at 1.45%, plus 0.9% on wages above the employer's $200,000 threshold. Enter year-to-date wages from before the current check.
- Traditional 401(k) deferrals stay subject to FICA. Health premiums under a Section 125 plan are assumed FICA-exempt.
- State withholding follows each supported state's table, with an actual state wage override available.
- Local, disability, and leave amounts are figures you enter, not calculated automatically.
- Annual projections repeat the current check. They do not apply full-year wage caps.
Annual-estimate mode
The separate annual-estimate mode is a legacy model built from a February 19 snapshot. It lacks later amendments, credits, and exemptions, so it is not a complete 2026 return calculator.
What is excluded
- Bonus and other supplemental wages
- Nonresident and multistate wages
- 2019-or-earlier W-4 forms
- District of Columbia withholding
Primary sources
- IRS Publication 15, Employer's Tax Guide
- IRS Publication 15-T, Federal Income Tax Withholding Methods
- IRS Tax Withholding Estimator
- SSA contribution and benefit base
Guide claims are checked against the applicable IRS, Social Security, Department of Labor, and state guidance. Each article identifies its sources and review date. We distinguish current employer tables from annual return rules and note effective dates and exceptions rather than filling gaps with invented rates. A source’s publication date and an article’s review date are different.
The state guide directory links all 50 existing state calculators. Dedicated articles are written for distinct payroll questions, not generated by replacing state names in a template. If an official source changes after an article’s review, check the agency’s current instructions before acting. These guides do not certify a return, worker classification, or withholding election.