Worked example: $3,200 of car loan interest (2026)
Single filer, $85,000 of wages, $3,200 of car loan interest, $9,000 withheld. This is the calculator’s starting point; change any box above to see your own figures.
| Line | Form 1040 | Amount |
|---|---|---|
| 1z | Wages, salaries, tips | $85,000 |
| 9 | Total income | $85,000 |
| 11a | Adjusted gross income | $85,000 |
| 12e | Standard deduction | $16,100 |
| 13a | Tips, overtime, car loan and senior deductions (Schedule 1-A) | $3,200 |
| 15 | Taxable income | $65,700 |
| 16 | Tax | $9,172 |
| 24c | Total tax | $9,172 |
| 25d | Federal income tax withheld | $9,000 |
| 33 | Total payments | $9,000 |
| 37 | Amount you owe | $172 |
Deduction and tax saved by income ($3,000, 2026)
The deduction is reduced by $200 for each $1,000 of modified AGI above $100,000 ($200,000 on a joint return).
| Income | Deduction (single) | Tax saved (single) | Deduction (joint) | Tax saved (joint) |
|---|---|---|---|---|
| $40,000 | $3,000 | $360 | $3,000 | $300 |
| $75,000 | $3,000 | $660 | $3,000 | $360 |
| $125,000 | $0 | $0 | $3,000 | $360 |
| $160,000 | $0 | $0 | $3,000 | $660 |
| $200,000 | $0 | $0 | $3,000 | $660 |
| $250,000 | $0 | $0 | $0 | $0 |
| $300,000 | $0 | $0 | $0 | $0 |
| $350,000 | $0 | $0 | $0 | $0 |
How your return is calculated
- Total income (line 9). Wages, interest, dividends, IRA and pension income, the taxable part of Social Security, capital gains (losses limited to $3,000) and Schedule 1 income such as self-employment profit and unemployment.
- Adjusted gross income (line 11). Total income minus half of self-employment tax, self-employed health insurance, HSA and deductible IRA contributions, educator expenses and student loan interest (up to $2,500).
- Deductions (lines 12–14). The larger of the standard deduction ($16,100 single, $32,200 joint, $24,150 head of household, plus $2,050 or $1,650 for age 65 or blindness) or your itemized deductions; then the qualified business income deduction and Schedule 1-A deductions for tips, overtime, car loan interest and seniors.
- Tax (line 16). From the IRS Tax Table below $100,000 of taxable income and the brackets above it. Qualified dividends and long-term gains go through the capital gain worksheet at 0%, 15% or 20%. Alternative minimum tax is added if it is higher.
- Credits (lines 19–21). Child and dependent care, education and saver’s credits, then the Child Tax Credit of $2,200 per child and $500 per other dependent, each limited to the tax.
- Other taxes (line 23). Self-employment tax, the 0.9% Additional Medicare tax and the 3.8% net investment income tax.
- Payments (lines 25–33). Withholding, estimated payments and the refundable credits: earned income credit, additional child tax credit (up to $1,700 per child) and 40% of the American opportunity credit.
- Refund or amount owed (lines 34–37). Payments minus total tax.
Key federal figures 2025 and 2026
| Item | 2025 | 2026 |
|---|---|---|
| Standard deduction (single / joint / head of household) | $15,750 / $31,500 / $23,625 | $16,100 / $32,200 / $24,150 |
| Extra standard deduction, 65+ or blind (married / unmarried) | $1,600 / $2,000 | $1,650 / $2,050 |
| Top of the 12% bracket (single / joint) | $48,475 / $96,950 | $50,400 / $100,800 |
| 0% capital gains up to (single / joint) | $48,350 / $96,700 | $49,450 / $98,900 |
| Child Tax Credit (refundable part) | $2,200 ($1,700) | $2,200 ($1,700) |
| Earned income credit, maximum (0 / 1 / 2 / 3+ children) | $649 / $4,328 / $7,152 / $8,046 | $664 / $4,427 / $7,316 / $8,231 |
| Tips deduction cap | $25,000 | $25,000 |
| Overtime deduction cap (single / joint) | $12,500 / $25,000 | $12,500 / $25,000 |
| Senior deduction per person 65+ | $6,000 | $6,000 |
| SALT cap | $40,000 | $40,400 |
| Social Security wage base | $176,100 | $184,500 |
| AMT exemption (single / joint) | $88,100 / $137,000 | $90,100 / $140,200 |
Official source: IRS 2025, IRS 2026. Rates checked on Oct 29, 2026.
Questions people ask
Which loans qualify?
Loans taken out after December 31, 2024 to buy a new (not used) car, minivan, van, SUV, pickup or motorcycle under 14,000 pounds, for personal use, secured by the vehicle, with final assembly in the United States. Leases do not qualify.
How do I prove it?
Lenders report the interest; you also enter the vehicle identification number on your return.
Do I need to itemize?
No. It is claimed on Schedule 1-A in addition to the standard deduction.
Is this the same as what tax software calculates?
It follows the same Form 1040 lines and IRS worksheets (Tax Table, qualified dividends and capital gain worksheet, Social Security benefits worksheet, Schedule 8812, EIC table). It does not cover every situation: foreign income, rental property, business assets, the premium tax credit and some credits are not included, and the QBI deduction assumes a business without employees.
Which tax year should I pick?
Pick 2026 for the return you file in early 2027, or to check now whether your withholding is on track. Pick 2025 to check a return for last year, for example if you filed for an extension or want to amend.
Reviewed by Soufyane S.. Last updated Oct 29, 2026. How we check numbers
Estimates for information only, not tax, legal or financial advice. Check with an adviser or the official tax authority.