Methodology & sources

A calculator is only as useful as its assumptions. This page lists the mathematical models, primary government sources, and testing behind SalarySteps.

Primary statutory sources (tax year 2026)

Tax estimates use the source figures below. Wage conversions do not calculate taxes unless explicitly stated:

• Federal Tax Brackets & Standard Deductions: IRS Revenue Procedure 2025-32 (annual cost-of-living adjustments for tax year 2026). Standard deductions: Single $16,100; Married Filing Jointly $32,200; Head of Household $24,150.
• Social Security Taxable Wage Base: Social Security Administration 2026 COLA Fact Sheet setting the maximum taxable earnings limit at $184,500 for the 6.2% Old-Age, Survivors, and Disability Insurance (OASDI) tax.
• Medicare Payroll Tax: Federal Insurance Contributions Act (FICA) establishing the 1.45% Medicare tax rate with no wage cap, and the Affordable Care Act (ACA) 0.9% Additional Medicare tax on single incomes exceeding $200,000.
• Supplemental Wage Withholding: IRS Publication 15 (Employer's Tax Guide), establishing the flat 22% federal withholding rate for bonuses and supplemental wages under $1,000,000.
• Overtime & Wage Standards: U.S. Department of Labor Fair Labor Standards Act (FLSA), 29 U.S.C. § 207, governing the standard 40-hour workweek and statutory 1.5x regular rate overtime compensation.

State estimates and source years

California and New York state income-tax estimates use the 2025 single-filer schedules in the model; federal estimates use 2026 figures. California SDI uses the published 2026 rate. These are simplified annual estimates, not complete employer withholding calculations. New York City estimates apply to residents. Benefit deductions and some state payroll programs are not modeled.

Check current instructions from California FTB, California EDD, and New York Tax Department when comparing your payslip.

How we test calculations

The weighted overtime calculator uses the ordinary federal weekly method described in DOL Fact Sheet 23, Fact Sheet 56A and Fact Sheet 56C. Straight-time earnings include all worked hours, eligible shift differentials and the includable bonus allocated to that week. The additional overtime premium is half the unrounded regular rate for hours over 40. The model excludes state daily overtime, special agreements and healthcare 8-and-80 schedules.

Each calculator is checked against hand-worked examples, bracket edges and wage caps before any change goes live. Results are calculated in your browser, so the numbers you enter stay on your device.

Core assumptions & modeling limits

Unless explicitly configured otherwise on a specific calculator, our baseline calculations assume:

• A single tax filer claiming the statutory standard deduction with zero dependents.
• A standard full-time work schedule of 40 hours per week for 52 weeks per year (2,080 annual hours).
• Exclusion of employer-specific pre-tax benefit elections (such as 401(k) contributions, HSA/FSA deferrals, and health insurance premiums) and post-tax garnishments.
• Divide-by-frequency payroll conventions: annual tax obligations divided by 26 for biweekly schedules, 24 for semi-monthly schedules, and 52 for weekly schedules.

Questions & source verification

Questions regarding our mathematical models or requests for custom verification should be directed to contact@pullmesh.com.