Calculator methodology and editorial standards

Numbriv provides scoped planning estimates with visible assumptions. Read the individual calculator’s sources, tax year and exclusions before comparing the result with a pay stub or return.

Publisher and responsibility

The publisher is Numbriv. The Numbriv editorial team maintains calculation code, source references and explanations. We do not claim that a licensed tax professional has reviewed every tool. Editorial responsibility and correction requests are available without an account.

What a review date means

A source-check date records when the cited rules were inspected. A formula test checks the implemented mathematics for stated cases. Neither proves that a user qualifies for an exemption or that every payroll exception is modeled. Pages whose full rule review is pending say so; a new build does not automatically create a new review date.

Annual tax and withholding are different

An annual rate-schedule estimate applies annual deductions, brackets and supported credits. Withholding follows an employer method and certificate settings and can intentionally use different thresholds or rates. Reviewed state pages label their method. An annual result divided by a pay frequency is an average unless the stated method also applies pay-period rounding. No result predicts a refund without actual withholding and the complete return.

Wages, benefits and overtime

Gross wages, income-tax wages and contribution-covered wages can differ. Qualified retirement, health and HSA amounts are handled only within each tool’s supported scope. A federal exclusion is not silently copied into a state program. Where a benefit-specific base remains unverified, the calculator rejects the unsupported automatic adjustment or requires an explicitly payroll-confirmed input.

Ordinary hourly overtime assumes a covered, nonexempt employee and one regular rate. California’s reviewed page uses already-classified daily, weekly and seventh-day totals. The federal overtime/tips deduction tool is separate from gross-pay math; deductions are not a general exemption from FICA.

Sources and testing

Tax parameters come from IRS, SSA and relevant government publications. Older publications keep their actual revision dates. Current state instructions take priority over stale summaries, and conflicts are recorded rather than resolved by guessing. Reference tests cover official examples, printed base amounts, rate boundaries, caps, invalid inputs and scope exclusions. Salary comparisons use the same engine as the calculator.

Privacy and commercial independence

Calculator inputs stay in the browser and are not included in calculator URLs or analytics events. Optional analytics require consent. Advertising and partner links cannot change assumptions, tax rates or numerical results. Read the privacy policy and advertising disclosure.

Updates and limits

The tax-rule review log records substantive changes. Unsupported jurisdictions, credits, other jobs, spouse earnings, local charges and special coverage are identified on each tool. Consult official employer resources and a qualified adviser when your situation falls outside the stated scope.