About this tool
The Qualified Business Income deduction created by the Tax Cuts and Jobs Act lets owners of pass through businesses deduct up to 20 percent of their qualified business income. The deduction is limited by overall taxable income and is phased out for specified service trades or businesses above income thresholds.
How it works
This calculator uses recent inflation adjusted thresholds: the SSTB phase out begins at roughly 200,000 single and 400,000 joint, with full phase out 50,000 above for single and 100,000 for joint filers.
How to use the Qualified Business Income Deduction Calculator
The Qualified Business Income Deduction Calculator is a browser-based tool that runs entirely on your device. Inputs you enter never reach a server - all calculations happen client-side in JavaScript. This means:
- Privacy: nothing is logged, sent, or stored by 3Tej. Inputs disappear when you close the tab.
- Speed: results update as you type. No network round trip.
- Offline use: once the page is cached, it works without internet.
- No signup: no account, no email, no rate limits.
Step by step
- Enter your inputs in the form above. Each field is labeled with its unit (currency, percent, kg, etc.) and the expected range.
- Read the result as it updates. The number reflects the formula commonly accepted in Qualified Business Income Deduction-related calculations.
- Adjust to see sensitivity: change one input at a time and watch how the output moves. This is the fastest way to understand which variable matters most.
- Copy or screenshot the result for later reference. The page state persists for the session if your browser allows it.
When you would use this
- Quick estimates: when you need a number now and don't want to open a spreadsheet.
- Sensitivity analysis: testing how a result changes as inputs vary, before committing to a real-world decision.
- Comparison: running the same calculation with different inputs to compare options side by side.
- Learning: building intuition for how the underlying math behaves.
- Documentation: capturing a snapshot of inputs and outputs at a point in time.
The formula explained
This calculator uses the following formula:
QBI Deduction = min(20% of QBI, 20% of (Taxable Income - Net Capital Gain)). For SSTBs above the threshold the QBI portion is reduced or eliminated.
The reason this formula works is rooted in the underlying physics, finance, or biology of the problem. Behind every calculator is a published, peer-reviewed equation or a widely accepted convention. We do not invent formulas; we apply standard ones from textbooks, government tables, professional bodies, and academic literature.
If you are curious about the math, the simplest way to verify is to plug in two known numbers and compare against a known result. The calculator should match published examples to within rounding precision.
Frequently asked questions
What is the QBI deduction?
The QBI deduction is a Section 199A pass through deduction that allows eligible self employed taxpayers to deduct up to 20 percent of qualified business income.
Who is eligible?
Owners of sole proprietorships, partnerships, S corporations, and certain trusts and estates can claim the QBI deduction subject to limits.
What is an SSTB?
A specified service trade or business includes fields like health, law, accounting, consulting, and athletics where the deduction is phased out at higher incomes.
What are the income thresholds?
Above the IRS thresholds the deduction phases out for SSTBs. The thresholds adjust annually for inflation; this tool uses recent inflation adjusted estimates.
Is the Qualified Business Income Deduction Calculator accurate?
The Qualified Business Income Deduction Calculator applies the standard formula for qualified business income deduction. Accuracy is limited only by your input precision. For decisions with material consequences, use the result as a starting point and verify with a qualified professional or the relevant official source.
Is the Qualified Business Income Deduction Calculator free?
Yes. 100% free, no signup, no payment, no API key. The site is funded by display ads that appear around the tool but not inside the calculation flow.
Are my inputs saved?
No. Inputs stay in your browser tab. Closing the tab discards them. The site uses Google Analytics for traffic measurement (anonymized) but does not see what you type into the form.
Can I use the Qualified Business Income Deduction Calculator on my phone?
Yes. The tool is responsive and tested on iOS Safari, Android Chrome, and major desktop browsers. Touch targets meet Apple's 44pt and Google's 48dp minimum guidance.
How do I report a bug or suggest improvement to the Qualified Business Income Deduction Calculator?
Email hi@3tej.com with the URL of this page and a description of what you saw vs expected. We typically respond within 72 hours and update calculators when rules or formulas change.
How accurate is the Qualified Business Income Deduction Calculator?
It applies the standard formula. Accuracy is limited only by your input precision. For decisions with material consequences (taxes, medical, legal, structural), use the result as a starting point and verify with a qualified professional in the relevant field.
Is the Qualified Business Income Deduction Calculator free to use?
Yes. 100% free, no signup, no payment, no API key. The site is funded by display ads around the tool but not inside the calculation flow.
Are my inputs saved anywhere?
No. All inputs stay in your browser tab. Closing the tab discards them. The site uses Google Analytics for traffic measurement (anonymized) but the analytics never see what you type into the form.
Does the Qualified Business Income Deduction Calculator work offline?
Yes. Once the page has loaded, it works without internet. The calculation runs in JavaScript on your device.
Can I share results from the Qualified Business Income Deduction Calculator?
Take a screenshot or copy the output. The page doesn't generate shareable URLs for specific calculations - inputs stay in your browser only.
Why are the results different from another qualified business income deduction tool?
Most likely: different formula assumptions, different default values, different rounding rules, or different applicable rates. Check the methodology if both tools document it. Both can be valid for different scenarios.