FAQ
What does this calculator estimate?
It estimates federal withholding on a bonus or other supplemental wage payment using the flat federal supplemental wage method described on the calculator page.
Does the site store my numbers?
No. The calculator runs locally in your browser and is designed as a no-account utility.
Does it include state taxes?
No. This is a federal-only estimate. State tax treatment varies and is outside the scope of this tool.
Does it include Social Security, Medicare, or deductions?
No. The output is intentionally narrow. It does not attempt to estimate payroll taxes, benefit deductions, retirement deductions, or employer-specific payroll handling.
Why does the federal rate change at high supplemental wage totals?
The methodology follows the standard threshold logic used for federal supplemental wage withholding. Once total supplemental wages exceed the high-threshold amount, the estimate uses 37% for the current bonus.
How can I ask about the site or partnerships?
Email [email protected].