Income Tax Calculator
Advanced salary paycheck calculator. Estimate Federal, State, and FICA taxes with 401k analysis, deductions, and breakdown by pay period (Weekly, Bi-Weekly, Monthly).
| Component | Amount | % of Gross |
|---|---|---|
| Net Pay | - | - |
Marginal Tax Rate: 0%.
This means any extra dollar you earn is taxed at this rate, not your entire income.
About
Calculating net income requires more than a simple percentage subtraction. The United States tax code utilizes a progressive tax system, meaning different portions of your income are taxed at increasingly higher rates. This tool provides a granular analysis of tax liability, incorporating Federal withholdings, FICA (Social Security and Medicare), and specific State income tax brackets for the 2024-2025 tax year.
Accuracy in tax planning is critical for liquidity management. Underestimating tax liability can lead to penalties, while overestimating results in an interest-free loan to the government. This application accounts for pre-tax contributions (such as Traditional 401k and IRA), which lower taxable income, and compares the Standard Deduction against custom itemized deductions. It is designed for employees who need to forecast their actual take-home pay across different payment frequencies, from weekly to annually.
Key features include: Marginal vs. Effective Rate analysis, Pre-tax deduction logic, Surtax calculations for high earners (Additional Medicare Tax), and a complete breakdown of state-specific liabilities.
Formulas
The core calculation for Federal Tax uses a summation of tiered brackets. Taxable Income (Itax) is derived first by subtracting pre-tax deductions and the standard deduction from Gross Income.
The Federal Tax (Tfed) is calculated using the bracket set B:
FICA taxes apply to Gross Income directly, not Taxable Income. Social Security is capped.
Reference Data
| Tax Component | Rate / Logic | 2024 Limits & Thresholds | Impact on Net Pay |
|---|---|---|---|
| Federal Income Tax | Progressive (10% to 37%) | 7 Brackets based on Filing Status | High |
| Social Security (OASDI) | 6.2% Flat | Wage Base Limit: $168,600 | Medium |
| Medicare | 1.45% Flat | No Limit | Low |
| Addt'l Medicare Tax | 0.9% Surtax | Income over $200,000 | Low (High Earners) |
| Standard Deduction (Single) | Fixed Amount | $14,600 | Reduces Taxable Income |
| Standard Deduction (Married) | Fixed Amount | $29,200 | Reduces Taxable Income |
| 401(k) Contribution | Voluntary Pre-Tax | Limit: $23,000 (under 50) | Lowers Tax Bill |