Federal Income Tax Estimate

Tax Planning
Updated Apr 2026 • Has calculator

Estimated US federal income tax owed for 2025 using progressive tax brackets and standard deduction.

Tax laws change annually and vary by country. The information on this page is for educational purposes only. Always verify figures with current official sources (IRS, HMRC, CRA, ATO) and consult a qualified tax professional before making any tax-related decision.

What is Federal Income Tax?

US federal income tax is calculated using a progressive bracket system—higher income is taxed at higher marginal rates, but only the income within each bracket is taxed at that rate. The 2025 tax brackets range from 10% to 37%. Most taxpayers claim the standard deduction ($15,000 for single, $30,000 for married filing jointly in 2025) to reduce taxable income. Effective tax rate—total tax divided by gross income—is always lower than the marginal rate.

Formula

Tax = Σ (income in each bracket × bracket rate)

Worked Example

Worked example — Single filer with $85,000 gross income — 2025

2025

Step 1  Gross income: $85,000 | Filing: Single | Standard deduction: $15,000
Step 2  Taxable income: $85,000 − $15,000 = $70,000
Step 3  10% on $0–$11,925: $1,192.50
Step 4  12% on $11,925–$48,475: $4,386.00
Step 5  22% on $48,475–$70,000: $4,735.50
Step 6  Total federal tax: $10,314 | Effective rate: 12.1%
Step 7  Marginal rate: 22% (rate on last dollar earned)

Source: IRS Rev. Proc. 2024-40 — 2025 Tax Inflation Adjustments (2024-10-22)

Calculate Federal Income Tax

Total gross income before deductions

0 = Single, 1 = Married Filing Jointly, 2 = Head of Household

1 = Yes (subtract standard deduction), 0 = No (gross income = taxable income)

Estimated Federal Tax

—

Not investment advice.

How to Interpret Federal Income Tax

< 5000
Very low tax — low income or many deductions
5000 – 15000
Low-moderate — effective rate under ~18%
15000 – 40000
Moderate-high — solidly in upper brackets
> 40000
High — top bracket territory

📚 Tax Basics — Complete the path

  1. Federal Income Tax
  2. Capital Gains Tax
  3. After-Tax Return
  4. Tax-Equivalent Yield
  5. Real Return
Sources
  1. IRS Rev. Proc. 2024-40 — 2025 Tax Brackets
  2. IRS — Tax Withholding Estimator