Kiddie Tax Calculator (Form 8615)

Find out whether a child's unearned income is taxed at the parent's rates under the kiddie tax, and how much extra tax that adds. Every step of Form 8615 shows, with its IRC §1(g) citation.

The exempt amount and rate tables change each year. Tax year 2025 follows the final Form 8615 instructions; tax year 2026 is a planning estimate. Last verified 2026-09-20.

The child

Tax year

2025 uses the final Form 8615 instructions. 2026 uses the published 2026 figures with the 2025 form's line structure.

Child's date of birth

A child who was born on January 1 counts as a year older at year end, and the calculator applies that rule.

Full-time student?

Matters only for ages 19 through 23.

Was the child's earned income more than half of the child's own support?

Matters for ages 18 through 23. Support counts everything spent on food, lodging, clothing, education, medical care, and similar needs, from any source. A scholarship is not support for a full-time student.

Child's earned income ($)

Wages, tips, and other pay for work performed.

Child's taxable unearned income ($)

Taxable interest, dividends, capital gains net of capital losses, and similar income. Leave out tax-exempt interest. The kiddie tax needs more than $2,700.

Qualified dividends included in that unearned income ($)

Form 1040 line 3a amounts, taxed at capital gain rates. Leave at zero if none.

Net capital gain included in that unearned income ($)

Long-term gains and capital gain distributions net of losses (Form 1040 line 7a, or the smaller of Schedule D lines 15 and 16). Leave at zero if none.

Was at least one parent alive at the end of the year?

Does the child file a joint return?

The parent's return

Parent's taxable income ($)

Form 1040 line 15 of the parent whose return applies. Married parents who file jointly use the joint return. Married parents who file separately use the parent with the greater taxable income. Divorced or never-married parents use the custodial parent, with exceptions.

Parent's filing status

Parent's qualified dividends ($)

Form 1040 line 3a of the same return. Leave at zero if none.

Parent's net capital gain ($)

Form 1040 line 7a, or the smaller of Schedule D lines 15 and 16. Leave at zero if none.

Other children using the same parent's return

If another child also files Form 8615 with this parent's information, run this calculator once for that child to get their line 5, and enter the total here. Leave all three at zero if there is no other child.

Their line 5 total ($)

Qualified dividends in it ($)

Their Line 5 Worksheet. This calculator's result shows it.

Net capital gain in it ($)

One case the calculator cannot finish

Does anyone's income include 28% rate gain or unrecaptured section 1250 gain, or does the return use Schedule J or Form 2555?

If yes, the calculator shows the child's net unearned income (line 5) and stops. Those cases use different tax worksheets.

How the kiddie tax works

The kiddie tax stops a parent from moving investment income to a child to use the child's lower tax brackets. When it applies, the child's unearned income above a small exempt amount is taxed at the parent's rates instead of the child's. IRC §1(g) sets the rule, and the child computes it on Form 8615.

Check whether the rule reaches the child. A child under 18 at year end is covered. A child who is 18 is covered unless earned income was more than half of the child's own support. A full-time student aged 19 through 23 is covered on the same support test. A child who is 24 or older is not. Either parent must be alive at year end, and the child must not file a joint return (IRC §1(g)(2)).
Check the unearned income. The child needs more than $2,700 of taxable unearned income for 2025. Unearned income is interest, dividends, capital gains, rents, royalties, trust income, the taxable part of Social Security and pensions, and similar income. Wages are earned income and stay out of it.
Find net unearned income. Subtract the $2,700 exempt amount, then cap the result at the child's taxable income (Form 8615 lines 1 through 5; IRC §1(g)(4)).
Tax that amount at the parent's rates. Add the net unearned income to the parent's taxable income, figure the tax, and subtract the parent's own tax. The difference is the tentative tax, which the Code calls the allocable parental tax (IRC §1(g)(3); lines 6 through 13).
Tax the rest at the child's rates, then take the larger result. The child's tax is the greater of two numbers: the tentative tax plus the tax on the child's remaining income, or the tax on all of the child's income at the child's own rates (IRC §1(g)(1); lines 14 through 18). The kiddie tax never lowers a child's tax.

When the income includes qualified dividends or net capital gain, Form 8615 taxes those parts at the lower capital gain rates: the tax on the parent's combined income and on the child's remaining income comes from the Qualified Dividends and Capital Gain Tax Worksheet, and the calculator shows each worksheet. When several children use the same parent's return, the tentative tax splits among them in proportion to their net unearned income.

The exempt amount, the rate tables, and the capital gain brackets are indexed for inflation, so they change from year to year. This calculator carries a separate set of figures for each tax year and shows the year it used.

Worked example

A 10-year-old earns $10,000 of interest and has no wages. The child's parent files as single with $120,000 of taxable income. Net unearned income is $7,300. Taxed at the child's own rates, the child would owe $868. The parent-rate rule raises that to $1,888, an extra $1,020.

Tax year 2025: the conditions, then Form 8615 line by line
Step	What it is	Amount	Source
Test 1	Unearned income more than $2,700Child’s unearned income $10,000 vs $2,700The $2,700 is twice the $1,350 §63(c)(5)(A) amount for 2025.	Met	Instructions for Form 8615, Who Must File; IRC §1(g)(2); Rev. Proc. 2024-40 §2.02
Test 2	Age and student testAge 10: under 18Under 18 at the end of 2025. Earned income and support do not matter for this arm.	Met	Instructions for Form 8615, Who Must File; IRC §1(g)(2); IRC §1(g)(2)(A)
Test 3	At least one parent alive at year endA parent was alive	Met	Instructions for Form 8615, Who Must File; IRC §1(g)(2); IRC §1(g)(2)(B)
Test 4	Child does not file a joint returnSeparate return	Met	Instructions for Form 8615, Who Must File; IRC §1(g)(2); IRC §1(g)(2)(C)
Test 5	Child is required to file a returnA dependent must file when unearned income is over $1,350Unearned income above $2,700 is already above $1,350, so a child who can be claimed as a dependent must file. This calculator assumes the child can be claimed as a dependent.	Met (assumed)	Pub. 501 (2025), dependents; Instructions for Form 8615, Who Must File
Line 1	Child’s unearned incomeAGI minus earned income (no adjustments assumed, so this equals the unearned income entered)Taxable unearned income only, net of capital losses; tax-exempt interest is not included.	$10,000	Form 8615 (2025), line 1; IRC §1(g)(4)(A)(i)
Line 2	Exempt amountChild does not itemizeThe sum of the two §1(g)(4)(A)(ii) terms: the $1,350 §63(c)(5)(A) amount, plus the greater of that amount or directly connected itemized deductions ($1,350 for a child who does not itemize).	$2,700	Form 8615 (2025), line 2; IRC §1(g)(4)(A)(ii)
Line 3	Unearned income above the exempt amountLine 1 − line 2	$7,300	Form 8615 (2025), line 3
Line 4	Child’s taxable incomeEarned + unearned income ($10,000) − dependent standard deduction ($1,350)The dependent standard deduction is the greater of $1,350 or earned income plus $450, capped at the basic amount (Rev. Proc. 2025-32 §3.01).	$8,650	Form 8615 (2025), line 4; IRC §63(c)(5)
Line 5	Child’s net unearned incomeSmaller of line 3 or line 4Net unearned income cannot exceed taxable income.	$7,300	Form 8615 (2025), line 5; IRC §1(g)(4)(B)
Line 6	Parent’s taxable incomeParent’s Form 1040, line 15 (zero if less)Single. Use the return of the parent named in the instructions for lines A–C.	$120,000	Form 8615 (2025), line 6; IRC §1(g)(3)(A)
Line 7	Other children’s net unearned incomeNo other child files Form 8615 for this parentLines 12a and 12b are skipped, and line 13 equals line 11.	Blank	Form 8615 (2025), line 7
Line 8	Parent’s income plus the children’s net unearned incomeLine 5 + line 6 + line 7	$127,300	Form 8615 (2025), line 8
Line 9	Tax on line 8 at the parent’s ratesSingle; Tax Computation Worksheet	$23,399	Form 8615 (2025), line 9; Rev. Proc. 2024-40 §2.01
Line 10	Parent’s tax on the parent’s own incomeSingle; from line 6The form takes this from the parent’s Form 1040 line 16, less any alternative minimum tax. The calculator computes it from line 6.	$21,647	Form 8615 (2025), line 10
Line 11	Tentative taxLine 9 − line 10The allocable parental tax: what the children’s net unearned income adds to the parent’s tax.	$1,752	Form 8615 (2025), line 11; IRC §1(g)(3)(A)
Line 13	Child’s share of the tentative taxLine 11 (line 7 is blank)	$1,752	Form 8615 (2025), line 13; IRC §1(g)(3)(B)
Line 14	Child’s taxable income above net unearned incomeLine 4 − line 5	$1,350	Form 8615 (2025), line 14
Line 15	Tax on line 14 at the child’s ratesSingle; Tax Table	$136	Form 8615 (2025), line 15; Rev. Proc. 2024-40 §2.01
Line 16	Tax with the parent-rate ruleLine 13 + line 15	$1,888	Form 8615 (2025), line 16; IRC §1(g)(1)(B)
Line 17	Tax at the child’s own ratesSingle; Tax Table on line 4	$868	Form 8615 (2025), line 17; IRC §1(g)(1)(A)
Line 18	Child’s taxLarger of line 16 or line 17Goes on the child’s Form 1040 line 16.	$1,888	Form 8615 (2025), line 18; IRC §1(g)(1)

Illustrative inputs. Sources: IRC §1(g); Instructions for Form 8615 (2025); Rev. Proc. 2024-40. Last verified 2026-09-20.

Common Questions

What is the kiddie tax?

A rule in IRC §1(g) that taxes a child's unearned income above $2,700 (for 2025) at the parent's rates when those rates are higher than the child's. It applies to children under 18, and to some 18-year-olds and full-time students through age 23. The child figures it on Form 8615.

What counts as unearned income?

Taxable interest, dividends, capital gains (including capital gain distributions), rents, royalties, pension and annuity income, unemployment compensation, the taxable part of Social Security, and income from a trust. Wages and other pay for work actually performed are earned income and do not count. Tax-exempt interest is not included because it is not taxable.

Which parent’s return do I use?

If the parents are married and file a joint return, use the joint return. If they are married and file separately, use the parent with the greater taxable income. If they are divorced, legally separated, or unmarried, use the custodial parent’s return. A remarried custodial parent’s new spouse takes the place of the other parent. Parents who never married but lived together all year use the parent with the greater taxable income. The Form 8615 instructions spell out each case.

Do the age and support tests change at 18?

Yes. Under 18, the rule applies. At 18, it applies only if the child’s earned income was not more than half of the child’s own support. From 19 through 23, it applies only to a full-time student who meets the same support test. At 24, it stops applying. A child born on January 1 counts as a year older at year end.

What if more than one of my children has unearned income?

Each child’s Form 8615 adds the other children’s net unearned income to the parent’s income (line 7) and then splits the tentative tax in proportion (lines 12a through 13). Run this calculator once for each child to get that child’s line 5, then enter the other children’s total in the form for each child. The result shows the qualified dividends and net capital gain inside line 5, which you can pass along the same way. Every child must use the same parent’s return.

What if the income is qualified dividends or long-term capital gains?

Enter the qualified dividends and net capital gain that sit inside the child’s unearned income. The calculator applies Line 5 Worksheet #1 to split them between the exempt amount and line 5, and then figures lines 9, 10, 15 and 17 with the Qualified Dividends and Capital Gain Tax Worksheet, which taxes the gains at 0%, 15% or 20%. Each worksheet shows under the table with every line.

What does the calculator not finish?

Four situations use different tax worksheets: 28% rate gain (collectibles, qualified small business stock), unrecaptured section 1250 gain, farming or fishing income under Schedule J, and a return with Form 2555. If you answer yes to that question, the calculator shows the child’s net unearned income (line 5) and stops.

Can the parent report the child’s income instead?

Sometimes. A parent can elect to report a child’s interest and dividends on the parent’s own return using Form 8814, which avoids a separate return and Form 8615 for the child. The federal tax can be higher under that election. This calculator does not model it.

Do the kiddie tax figures change every year?

Yes. The exempt amount and the rate tables are indexed for inflation. This calculator carries the figures for each tax year it supports and shows which year it used.

Is this calculator free?

Yes. It is free, with no signup, and it shows every Form 8615 line with its citation.

Download the Kiddie Tax Calculator Compliance Card (PDF) — for your §10.36 AI-tool file