How this calculator works
This income tax estimator starts with your annual gross income and subtracts pre-tax deductions you enter—401(k), HSA, and other pre-tax items—to approximate adjusted gross income (AGI). It then applies either the 2025 standard deduction for your filing status or your itemized deduction total to arrive at federal taxable income.
Federal income tax is calculated with 2025 IRS marginal brackets at 10%, 12%, 22%, 24%, 32%, 35%, and 37%. The results table shows how much income falls in each bracket and the tax assigned to each slice. A simplified child tax credit ($2,000 per dependent entered) reduces federal tax up to the amount otherwise owed.
State income tax uses an approximate effective rate for the state you select. Real state returns may use progressive brackets, local taxes, credits, and different rules for retirement income—state results are labeled as estimates.
This tool does not include FICA (Social Security and Medicare), self-employment tax, alternative minimum tax, capital gains preferential rates, or every credit and phase-out on a full return. Salary and wage income with ordinary bracket treatment is the sweet spot. It is a planning estimate, not tax advice.
For paycheck-level take-home that includes FICA, use the paycheck calculator. To see how retirement deferrals affect long-term savings, try the 401(k) contribution calculator. For investment sales taxed at capital gains rates, use the capital gains tax calculator.
What affects the result
Income tax estimates change with filing status, deductions, credits, and income composition.
- Filing status sets bracket widths and the standard deduction ($15,000 single, $30,000 married filing jointly, $22,500 head of household, $15,000 married filing separately in 2025).
- Pre-tax deductions lower federal taxable income. Traditional 401(k) and HSA contributions are the most common examples modeled here.
- Standard vs. itemized — itemize only when your Schedule A total exceeds the standard amount for your status.
- Dependents — each dependent entered applies up to $2,000 of child tax credit against federal tax in this simplified model. Phase-outs at higher incomes are not fully modeled.
- State selection — progressive states can owe much more or less than a flat effective estimate; zero-tax states show $0.
Marginal rate is the bracket on your last dollar of taxable income. Effective rate is federal tax divided by gross income—usually lower because early dollars are taxed at lower brackets.
W-2 wage income fits this model well. Large long-term capital gains, self-employment income, or rental property may need specialized tools and professional review.
Real-world examples
Example 1: Single filer, W-2 income. You earn $85,000, contribute $6,000 to a traditional 401(k), take the standard deduction, live in Texas (no state income tax), and claim 0 dependents. Taxable income is roughly $64,000. Federal tax falls across the 10%, 12%, and 22% brackets; after-tax income is gross minus 401(k) minus estimated federal tax.
Example 2: Married filing jointly with children. $140,000 gross, $10,000 combined 401(k), standard deduction, 2 dependents, Illinois. Taxable income is reduced by the $30,000 standard deduction and pre-tax deferrals. Federal tax is lowered by up to $4,000 of child tax credit. Illinois applies an approximate state rate on adjusted gross income.
Example 3: Itemized deductions. A homeowner in California with $180,000 gross might itemize $32,000 in mortgage interest, taxes, and charity instead of the standard deduction if itemized exceeds standard. Switch deduction type in the calculator to compare outcomes.
Example 4: Pre-tax HSA. Adding $4,300 in HSA deferrals (2025 self-only limit) on top of 401(k) contributions further lowers taxable income and estimated federal tax. See the HSA calculator for growth projections on those contributions.
Example 5: Raise planning. A $10,000 raise from $90,000 to $100,000 may push part of your income into a higher bracket without taxing all earnings at that rate. Run both scenarios to estimate withholding adjustments before year-end.
Common mistakes
Confusing marginal and effective rates. Being in the 22% bracket does not mean all income is taxed at 22%. Only dollars above the prior bracket threshold are taxed at 22%.
Ignoring pre-tax benefits. Health insurance premiums and FSA contributions reduce taxable wages but are easy to omit from annual totals when estimating from gross alone.
Assuming state estimate equals your return. High-income filers in progressive states often pay more than a mid-range effective rate; local city taxes are not modeled here.
Expecting FICA in this result. Payroll taxes are separate. Compare with the paycheck calculator for per-period net pay including Social Security and Medicare.
Itemizing when standard is higher. Many filers use the standard deduction because limits on state and local tax deductions and other rules make itemizing less common unless mortgage interest and charity are substantial.
Using this tool for capital gains-heavy returns. Investment sales taxed at 0%, 15%, or 20% federal rates need the capital gains tax calculator or the guide on holding periods and basis—not ordinary bracket math alone.
When to use this calculator
Use this estimator when planning annual taxes from salary income—evaluating a raise, comparing filing statuses, or seeing how much a 401(k) or HSA increase saves in federal tax. It helps before year-end when adjusting withholding or deferrals.
Pair results with the budget calculator to translate after-tax income into monthly spending buckets. Read the take-home pay explained guide for how withholding differs from this annual view.
Use the Roth vs. traditional IRA calculator when pre-tax deferrals shown here should be weighed against Roth contributions for long-term tax diversification.
Skip this tool for self-employment schedules, large capital gains, multi-state allocation, or situations needing AMT or NIIT modeling—those require a full preparer or specialized software.
Related calculators
- Paycheck / take-home pay calculator — estimate net pay per period including FICA and state withholding-style inputs.
- 401(k) contribution calculator — model employer match and contribution limits alongside retirement growth.
- Roth vs. traditional IRA calculator — compare after-tax value of Roth and traditional retirement savings.
- Capital gains tax calculator — estimate tax on investment sales at preferential short- or long-term rates.
- Budget (50/30/20) calculator — divide after-tax income into needs, wants, and savings.
Related guides
- Take-home pay explained — how gross pay becomes net pay beyond income tax alone.
- Roth vs. traditional IRA — when pre-tax vs. Roth contributions may make sense given your bracket.
- How capital gains tax works — short- vs. long-term rates and holding periods this income tax tool does not model.
- The 50/30/20 budget rule — a simple framework for spending after-tax income.
FAQ
What is the difference between effective and marginal tax rate?
Your marginal rate is the tax rate on your next dollar of taxable income—the bracket you are in. Your effective rate is total federal income tax divided by gross income (or total income), which is usually lower because lower brackets tax the first dollars earned.
Does this calculator include FICA (Social Security and Medicare)?
No. This tool estimates federal and state income tax only. Social Security, Medicare, and additional Medicare tax are payroll taxes handled separately. Use the paycheck calculator for take-home pay that includes FICA.
How does filing status affect my tax?
Filing status sets your standard deduction and tax bracket thresholds. Married filing jointly generally has wider brackets and a larger standard deduction than single filers. Married filing separately often faces tighter brackets and lost credits compared with joint filing.
What is a standard deduction vs. itemized deduction?
The standard deduction is a fixed amount that reduces taxable income with no receipts required. Itemized deductions sum eligible expenses such as mortgage interest, charitable gifts, and state and local taxes (subject to caps). You benefit from itemizing only when the total exceeds the standard deduction.
Does pre-tax 401(k) contribution reduce my taxable income?
Yes. Traditional 401(k) deferrals reduce wages for federal income tax in this model. They still reduce take-home pay because the money is saved in your retirement account rather than paid to you as cash.
Why does the state tax show as estimated?
State rules vary widely—progressive brackets, local taxes, credits, and different treatment of retirement income. This calculator applies an approximate effective rate by state for planning, not a line-by-line state return.
Which tax year does this calculator use?
Federal brackets and standard deductions reflect 2025 IRS inflation-adjusted amounts. Tax law can change; verify figures before filing.
Does this model the child tax credit?
Yes, in simplified form. Each dependent entered reduces estimated federal tax by up to $2,000 per qualifying child, capped at the tax otherwise owed. It does not model phase-outs, other dependents credits, or refundable portions in detail.