True Marginal Tax Rate Calculator
Your real next-dollar tax rate stacks federal bracket + state + FICA + NIIT + Additional Medicare + Social Security cascade. The headline bracket is a lie — see what you actually pay.
All inputs adjust the result in real time. No data leaves your browser.
When people talk about being 'in the 32% bracket,' they're missing 4-6 additional layers of tax that stack on top of the federal bracket. Your actual marginal rate — the tax cost of your next dollar of income — combines federal income tax, state tax, FICA (Social Security + Medicare), the 0.9% Additional Medicare Tax (above $200K), the 3.8% Net Investment Income Tax (above $200K/$250K MAGI), and for retirees, the Social Security taxation cascade.
This calculator computes your true marginal rate by simulating an additional $1,000 of W-2 wage income and measuring the actual incremental tax across all of these layers, using 2026 IRS bracket data, your selected state's tax rate, and the FICA/NIIT/Additional Medicare thresholds.
For high earners ($300K+) in high-tax states, the true marginal rate often exceeds 45-50% — meaningfully higher than the 32-35% federal bracket alone. For retirees claiming Social Security, every additional dollar of pension/IRA withdrawal can also push more SS into the taxable category, creating an effective marginal rate that can exceed 40% even in middle brackets.
Knowing your true marginal rate matters for: Roth conversion timing, deferred compensation decisions, charitable giving timing, bonus negotiation, and any decision where you're weighing an additional dollar of income against an alternative use of the money. The 'I'm in the 24% bracket so this raise costs me $760 of $1,000' calculation is often substantially wrong.