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Taxes · Income Tax

1040 Federal Income Tax Calculator

Estimate your federal income tax, taxable income, and effective and marginal rates.

  • Free to use here · embed on the Business plan
  • 5 inputs · 5 results
  • English & Spanish

Try the 1040 Federal Income Tax Calculator

Estimate your federal income tax — results update as you type.

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Estimates only — not a loan offer or financial advice.

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What this calculator does

What the 1040 Federal Income Tax calculator works out

The 1040 Federal Income Tax Calculator is a free, embeddable calculator from CalcFunnel. Estimate your federal income tax, taxable income, and effective and marginal rates.

You enter 5 inputs: filing status, gross income, adjustments (pre-tax), itemized deductions and tax credits.

It returns federal tax, taxable income, effective tax rate, marginal tax rate and after-tax income.

Built for tax preparers, CPAs and payroll firms. Embedding it on your own website needs the Business plan (from $210/month, with a 14-day free trial), which unlocks the Taxes category.

Results it shows

  1. 01Federal Tax
  2. 02Taxable Income
  3. 03Effective Tax Rate
  4. 04Marginal Tax Rate
  5. 05After-Tax Income

The first figure — federal tax — is the headline result.

Inputs

The inputs it uses

Each field below comes straight from the calculator, with the same help text visitors see when they hover the info icon.

Income

Filing Status
Your federal filing status, which sets your brackets and standard deduction. A qualifying surviving spouse uses Married Filing Jointly.Options: Single · Married Filing Jointly · Married Filing Separately · Head of Household
Gross Income
Your total income for the year before adjustments.
Adjustments (pre-tax)
Above-the-line adjustments like traditional 401(k)/IRA or HSA contributions, subtracted to get AGI.

Deductions & Credits

Itemized Deductions
Total itemized deductions (mortgage interest, state and local taxes up to the $40,400 SALT cap for 2026, charity…). The larger of this or the standard deduction is used.
Tax Credits
Nonrefundable credits (e.g. the child tax credit) that reduce tax dollar-for-dollar.

For your website

Embed this calculator on your website

Put the 1040 Federal Income Tax Calculator on your own site with your colors, copy and lead form. Every calculation can arrive in your CRM with the numbers attached.

Works on WordPress, Wix, Squarespace, Webflow, Shopify, GoHighLevel and plain HTML — paste one line into an HTML or code block. No plugin needed.

Start free How embedding works

Free plan, no card. 14-day trial on Pro & Business.

  1. Inline on any pagePaste the snippet where the calculator should appear. It fills the width of its container and resizes to fit its content.
  2. Popup buttonA button sits on your page; visitors click it and the calculator opens in a popup.
  3. Floating corner widgetPaste once — or in your site-wide footer code — to show a floating calculator bubble in the corner of every page.
  4. Open from your own link or buttonGive any existing link, button or image a class and it opens the calculator when clicked.
  5. Direct linkA full-page link to the calculator for emails, social posts, QR codes or a menu item.

FAQ

1040 Federal Income Tax calculator FAQs

Still stuck? Ask the team — we reply within one business day.

Q.01What does the 1040 Federal Income Tax Calculator calculate?
Estimate your federal income tax, taxable income, and effective and marginal rates. It returns federal tax, taxable income, effective tax rate, marginal tax rate and after-tax income.
Q.02What information do I need to use the 1040 Federal Income Tax Calculator?
You enter 5 inputs: filing status, gross income, adjustments (pre-tax), itemized deductions and tax credits. Every input starts with a sensible default, so you can change only what you know.
Q.03What does “Filing Status” mean in the 1040 Federal Income Tax Calculator?
Your federal filing status, which sets your brackets and standard deduction. A qualifying surviving spouse uses Married Filing Jointly.
Q.04What does “Gross Income” mean in the 1040 Federal Income Tax Calculator?
Your total income for the year before adjustments.
Q.05Is the 1040 Federal Income Tax Calculator free to use?
Yes — you can use it on this page for free, without an account. Embedding it on your own website needs the Business plan (from $210/month, with a 14-day free trial), which unlocks the Taxes category. Compare plans.
Q.06Can I embed the 1040 Federal Income Tax Calculator on my website?
Yes. Embed it inline, as a popup button, as a floating corner widget, from your own link or button, or share a direct link. It works on WordPress, Wix, Squarespace, Webflow, Shopify, GoHighLevel and plain HTML sites with one line of code — see embedding.
Q.07Is the 1040 Federal Income Tax Calculator available in Spanish?
Yes. Labels, tooltips and result names are available in English and Spanish, and visitors can switch language in the calculator.
Q.08Can the calculator capture leads?
Yes. It can end with a lead form, a Get a Quote form, a Share panel or a button to any URL. Leads are saved with the inputs and results attached and can be forwarded to your CRM by webhook.
Q.09Are the 1040 Federal Income Tax results financial advice?
No. Estimates only. Uses 2026 federal tax brackets and standard deductions (IRS Rev. Proc. 2025-32); it does not include state tax, payroll (FICA) tax, capital-gains rates, the additional deductions for age 65+, the many credits/phase-outs, or AMT. Not tax advice — consult a tax professional.

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The 1040 Federal Income Tax Calculator is one of 188 calculators you can brand and embed with one line of code.

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