Calculate federal income tax for an individual taxpayer. Supports TY2024 through TY2026. Includes bracket breakdown, effective/marginal rates, SE tax, NIIT, Additional Medicare Tax, QBI deduction, capital gains, and child tax credit. All calculations run locally — no data is sent to any server.

Get federal income tax brackets and standard deduction for a given tax year and filing status.

Compare tax liability across different filing statuses for the same income. Helps determine the most advantageous filing status.

Calculate estimated quarterly tax payments (Form 1040-ES) for self-employed or other taxpayers who need to make estimated payments.

Calculate combined federal + state tax for a complete picture of total tax liability. Returns federal breakdown, state tax, and combined totals in one call.

Calculate recommended W-4 withholding settings. Estimates per-paycheck federal tax and provides step-by-step W-4 form recommendations.

List available tax deductions with eligibility rules and limits. Covers both above-the-line and itemized deductions.

Compare standard deduction vs itemized deductions to determine which is more beneficial.

Get important IRS tax deadlines and due dates for a given tax year.

Provide instructions on how to check IRS refund status. This tool does NOT access your IRS account — it provides the official links and requirements.

Get information about common IRS tax forms — what they are, who needs them, and where to find them.

List available federal tax credits with eligibility, amounts, and phase-out rules. Covers family, education, energy, retirement, healthcare, and income-based credits.

Check which tax credits you may be eligible for based on your situation.

Get details on retirement account types — contribution limits, tax treatment, income limits, and tips.

Get detailed info on tax-advantaged retirement strategies like Backdoor Roth, Mega Backdoor Roth, Roth Conversion Ladder, Tax Loss/Gain Harvesting.

Calculate the exact Earned Income Tax Credit (EITC) amount. The EITC is one of the largest refundable credits for low-to-moderate income workers.

Get state income tax information — rates, brackets, and key details for any US state.

Estimate state income tax using an explicit tax-year calculation profile. Unsupported state-year paths fail closed.

Compare state income tax for one tax year only when every requested state has an explicit calculation profile.

List all US states with no state income tax.

Get personalized year-end tax optimization strategies based on your income, deductions, and situation. Suggests actions to reduce tax liability before year-end.

Compare tax liability across different tax years for the same income. Shows how bracket changes and inflation adjustments affect your tax.

Detailed self-employment tax breakdown including Schedule C profit, SE tax, QBI deduction, and recommended quarterly payments. Above the annual QBI threshold, provide SSTB classification, W-2 wages, and qualified-property basis, using 0 where none apply.

Analyze the tax benefit of mortgage interest deduction and property taxes. Compares itemizing with mortgage vs taking the standard deduction.

Compare education tax benefits: AOTC vs Lifetime Learning Credit, student loan interest deduction, and 529 plan advantages.

Compare Married Filing Jointly (MFJ) vs Married Filing Separately (MFS). Shows tax difference and lists all MFS restrictions that may affect your situation.

Calculate all OBBB (One Big Beautiful Bill) new deductions for TY2025+: tips income deduction, overtime pay deduction, senior bonus deduction, and auto loan interest deduction. Shows which deductions you qualify for and the total tax savings.

Show all differences between two tax years — bracket changes, deduction limits, credit amounts, SALT cap, CTC, and new OBBB provisions. Great for understanding how tax law changes affect you.

Generate a detailed tax estimate combining federal tax, supported state tax, FICA, modeled credits, deductions, take-home pay, and refund inputs.

Process multiple 1099 forms and calculate the tax impact of each income type. Handles 1099-NEC (freelance), 1099-INT (interest), 1099-DIV (dividends), 1099-B (investments), 1099-MISC.

Generate a personalized tax calendar based on your situation. Shows deadlines for filing, estimated payments, extensions, and key actions.

Analyze a paycheck to verify withholding accuracy. Input your pay stub numbers and see if your employer is withholding the right amount.

What-if tax scenario simulator. Compare your current situation against a hypothetical change: income change, relocation, Roth conversion, filing status change, etc. Shows the exact tax impact of the change.

Evaluate your IRS audit risk based on your tax return profile. Identifies red flags, scores your risk level, and provides tips to reduce audit exposure.

Generate a personalized checklist of tax documents you need to gather for filing. Based on your income sources, deductions, and life events.

Analyze investment lots and suggest which to sell to minimize tax. Considers long-term vs short-term, 0% bracket space, loss harvesting, and wash sale rules.

Plan tax-efficient retirement withdrawals. Determines optimal order to draw from Traditional IRA, Roth IRA, and taxable accounts to minimize lifetime tax.

Create a 3-5 year tax projection and strategy. Models income changes, Roth conversions, retirement contributions, and bracket management across multiple years.

In-depth relocation tax analysis using exact-year state profiles. Additional projection years require explicit annual federal and state data.

One-click tax health check. Analyzes your full financial picture and outputs a report with actionable findings: missed credits, withholding accuracy, deduction optimization, audit risk, retirement savings gaps, and year-end planning tips.

Look up IRS tax rules, definitions, and common questions. Covers filing rules, income types, deduction rules, credit eligibility, stock options, wash sales, and more.

Step-by-step guide for filling out a specific IRS form or schedule. Explains each section, what data you need, and common mistakes to avoid.

Generate a pre-filled GitHub Issue URL for reporting calculation errors or data issues. No data is sent. The user clicks the link to submit. Use this after verifying the user's inputs.

Generate a deterministic, privacy-first local tax plan with structured results, assumptions, source provenance, calculation trace, and explicit unsupported boundaries.