Methodology review: October 2026
How to Use the Federal Income Tax & Deduction Calculator
- Enter your annual gross W-2 wages or salary before any deductions.
- Select your filing status: single, married filing jointly, married filing separately, or head of household.
- Enter income-tax deductions such as traditional 401(k) contributions or direct deductible HSA contributions. For FICA-exempt payroll benefits, use the paycheck calculator.
- Enter your eligible itemized deduction total to compare it with the standard deduction. You can leave it at zero to use the standard deduction automatically.
- Add other ordinary income such as taxable interest. Self-employment profit and preferential-rate capital gains are not supported. You may also enter a flat state tax rate for a rough estimate.
- Review your results: federal tax owed, effective and marginal tax rates, FICA taxes, and take-home pay. Example: a single filer earning $85,000 with $6,500 in pre-tax contributions owes about $8,440 in federal income tax plus roughly $6,503 in FICA, leaving about $63,558 a year ($5,296 a month) after the contribution and estimated federal taxes.
What This Calculator Does
Enter a total for itemized deductions you can claim, or leave it at zero. The calculator uses whichever is larger: that total or the 2026 standard deduction for your filing status. It then estimates federal income tax, FICA payroll taxes, take-home pay, and effective and marginal tax rates. It does not determine eligibility for individual deductions or credits.
The result is driven mainly by four inputs: your gross income, filing status, pre-tax deductions, and whether you itemize or take the standard deduction. For 2026, the standard deduction is $16,100 for single filers and $32,200 for married filing jointly. Because the US income tax system is progressive, only the income within each bracket is taxed at that bracket's rate.
Use this calculator to estimate how a raise, bonus, or 401(k) contribution changes your federal tax and take-home pay. The extra-income input adds ordinary income tax but does not calculate self-employment tax or preferential-rate capital gains. Use the quarterly estimated tax calculator for freelance earnings.
Formula
Tax = Σ [bracket portion of taxable income × bracket rate], plus FICA = (wages × 6.2%, capped) + (wages × 1.45%)Taxable income is calculated as gross income minus pre-tax deductions (401k, HSA) minus the standard or itemized deduction (whichever is higher). Federal tax is then computed by applying each bracket's rate only to the income that falls within that bracket. FICA taxes are calculated separately on gross wages: Social Security at 6.2% up to the annual wage base ($184,500 for 2026), and Medicare at 1.45% on all wages (plus an additional 0.9% above $200,000 single / $250,000 married).
- AGIAdjusted gross income — gross income minus pre-tax deductions
- Taxable IncomeAGI minus the standard (or itemized) deduction
- Marginal RateThe tax rate applied to your last dollar of taxable income
- Effective RateFederal income tax ÷ total entered income; FICA and state tax are shown separately
Examples
Example 1: Single filer, $85,000 salary, $6,500 to 401(k)
AGI = $78,500. Standard deduction (single, 2026) = $16,100. Taxable income ≈ $62,400.
Federal income tax ≈ $8,440, with a 22% marginal bracket. FICA ≈ $6,503 on gross wages. After the $6,500 pre-tax contribution, estimated take-home is about $63,558/year, or $5,296/month.
Example 2: Married filing jointly, $150,000 combined income
No pre-tax deductions. Standard deduction (MFJ, 2026) = $32,200. Taxable income ≈ $117,800.
Federal income tax ≈ $15,340, with a 22% marginal bracket. FICA ≈ $11,475. Estimated take-home is about $123,185/year, or $10,265/month.
Example 3: High earner hitting the Social Security wage base
Single filer, $250,000 salary, $0 pre-tax deductions, standard deduction $16,100. Taxable income ≈ $233,900.
Federal income tax ≈ $51,304, with a 32% marginal bracket. Social Security tax caps at $184,500 × 6.2% = $11,439. Medicare including Additional Medicare Tax is about $4,075. Estimated take-home is about $183,182/year.
Key Terms Explained
- Marginal Tax Rate
- The tax rate applied to your last dollar of income — your top tax bracket. It's higher than your effective (average) rate.
- Effective Tax Rate
- Your total tax divided by your total income — the average rate you actually pay across all brackets.
- Standard Deduction
- A fixed amount you can subtract from income before tax instead of itemizing. Most filers take the standard deduction.
- FICA Taxes
- Payroll taxes for Social Security (6.2%) and Medicare (1.45%) withheld from wages, separate from federal income tax.
- Traditional IRA
- A retirement account funded with pre-tax (or deductible) dollars. Contributions may lower your taxable income today, but withdrawals in retirement are taxed as ordinary income.
- Employer Match
- Money your employer adds to your 401(k) based on your own contributions — effectively free retirement savings, up to a limit.
Sources and methodology
How SmartRates checks calculations · About the editorial team
Methodology
Payroll benefits exempt from FICA are not modeled here; use the paycheck calculator for those benefits. Self-employment tax and preferential capital-gains rates are excluded. This calculator applies the 2026 IRS progressive tax brackets to your taxable income, then layers on FICA payroll taxes — 6.2% Social Security up to the annual wage base and 1.45% Medicare on all wages, plus a 0.9% surtax above the high-earner threshold — to estimate your total federal tax burden and take-home pay. Figures follow IRS Revenue Procedure guidance and are for planning purposes only; consult a tax professional or the IRS for your exact liability.
Frequently Asked Questions
What are the 2026 federal income tax brackets?+
For 2026, the seven rates remain 10%, 12%, 22%, 24%, 32%, 35%, and 37%. Single filers enter the 22% bracket above $50,400. Source: IRS Revenue Procedure 2025-32.
What is the 2026 standard deduction?+
Single: $16,100 · Married Jointly: $32,200 · Head of Household: $24,150 · Married Separately: $16,100.
Does this calculator find every tax deduction?+
No. Enter a total for itemized deductions you have already determined you can claim. The calculator compares that total with the 2026 standard deduction for your filing status and uses the larger amount. It does not determine eligibility for each deduction or tax credit.
What is FICA tax?+
Social Security: 6.2% on wages up to $184,500. Medicare: 1.45% on all wages, plus 0.9% above the applicable threshold.
How do I calculate my take-home pay from my salary?+
Take-home pay equals your gross salary minus pre-tax deductions, federal income tax, FICA taxes (Social Security and Medicare), and estimated state tax if entered. This calculator shows both annual and monthly estimates.
Does this calculate self-employment tax on freelance income?+
No. The extra-income input can estimate federal income tax on other taxable income, but it does not add self-employment tax or investment-specific taxes. Use the quarterly estimated tax calculator for net self-employment earnings.
What's the difference between AGI, taxable income, and gross income?+
Gross income is your total earnings before any deductions. Adjusted gross income (AGI) is gross income minus above-the-line deductions like pre-tax 401(k) or HSA contributions. Taxable income is AGI minus the standard deduction (or itemized deductions, whichever is greater) — it's the figure your federal tax bracket rates are actually applied to.
When does Additional Medicare Tax apply?+
The additional 0.9% applies to wages above $200,000 for single and head-of-household filers, $250,000 for married filing jointly, and $125,000 for married filing separately. Regular Medicare tax is 1.45% on all wages; unlike Social Security tax, it has no wage cap.
Can I save my results?+
Yes. Use “Save” to store a snapshot; click “Saved” to remove it. Without an account it remains in this browser. If you log in, saved scenarios sync securely to your SmartRates account so they are available on your other devices.
How do I share my calculation?+
Click “Share” in the toolbar to copy a link (or open your device’s share sheet). The link encodes your exact inputs, so whoever opens it sees the calculator pre-filled with the same numbers and the same result.
Can I email my calculator results?+
Yes. Click “Email” to open your configured email app with the recipient blank and the subject and plain-text report filled in. Long reports use a summary and a link; use Export PDF for the complete report. Add a recipient and review before sending.
Can I export or print my results as a PDF?+
Yes. Click “Export PDF” to open a clean, printable summary of your inputs and results that you can save as a PDF or print. It includes a timestamp and a link back to the calculator.
How accurate are the calculator results?+
The arithmetic follows the formula and assumptions documented on this page. The result is still an estimate because actual rates, fees, taxes, timing conventions, eligibility rules, and provider calculations can differ. Use figures from your official quote, statement, contract, or tax form before making a financial decision.
Which inputs have the biggest effect on the result?+
Rate, time, starting balance, recurring payments or contributions, and fees usually have the largest effects. Change one input at a time to create a conservative, expected, and optimistic scenario instead of relying on a single forecast.
Are taxes, fees, and inflation included?+
Only when they appear as an input or are explicitly described in the methodology. Do not assume an omitted cost is zero. Review the formula and methodology sections to see exactly what is included before comparing the result with an outside quote.
Can this calculator predict future rates or returns?+
No. A calculator projects the assumptions entered; it cannot predict market returns, inflation, variable interest rates, tax-law changes, or provider decisions. Rerun the calculation with several assumptions to understand the range of possible outcomes.
Why might my lender, bank, broker, or tax software show a different result?+
Professional systems may use daily timing, transaction dates, compounding conventions, rounding rules, account-specific fees, credits, eligibility details, or regulations that a general-purpose calculator cannot know. A small difference can be rounding; a large difference usually means an assumption or included cost is different.
Disclaimer: Calculations are for informational purposes only and do not constitute professional financial advice. Please consult with a certified professional before making financial decisions.