How to use this calculator
- Choose the tax year and your filing status, tick whether you're 65 or older, and enter your children under 17.
- Tick each kind of income you have this year and enter the amounts: wages, self-employment profit, pensions and retirement withdrawals, Social Security, and investment income.
- Choose what your next dollar is (a raise, side income, a withdrawal, interest or a long-term gain) and how much of it to price. The default is $1,000.
- Read your bracket, your true marginal rate on that amount, and your average rate. Open the tables below the chart to see where the money goes and which income lines are close.
- Under More options, add pre-tax 401(k) contributions, tax-exempt interest, adjustments, itemized deductions, and older children or other dependents.
The numbers already filled in are an example. Replace them with your own.
How it's calculated
The calculator builds your federal return in the order of Form 1040: your income, less adjustments, is your adjusted gross income; less the standard deduction (or your itemized deductions, if larger), it is your taxable income. Ordinary income fills the brackets first, and qualified dividends and long-term gains sit on top at 0%, 15% or 20%. Then come the child tax credit and the earned income credit, Social Security and Medicare, and the other federal taxes. Then it adds your next amount and does it all again. The difference is what that amount costs.
Your bracket fills from the bottom
Say you file single for 2026 with $70,000 of wages. After the standard deduction your taxable income is $53,900: $12,400 at 10%, $38,000 at 12%, and $3,500 at 22%. That makes 22% your tax bracket, with $51,800 of room before the next one. Under $100,000 of taxable income the IRS Tax Table sets the tax, as on the return: $6,576. Add $5,355 of Social Security and Medicare and your federal taxes come to $11,931, 17.04% of your income: your average rate.
Your next $1,000 of wages adds $220 of income tax and $76.50 of Social Security and Medicare: $296.50, a true marginal rate of 29.65%.
Social Security and the senior deduction
Up to 85% of Social Security benefits are taxable, depending on your provisional income. Inside that range each extra dollar of other income makes more of your benefits taxable. A 67-year-old with $30,000 of Social Security, a $35,000 IRA withdrawal and $5,000 of qualified dividends is in the 12% bracket, yet the next $1,000 from the IRA makes $850 more of their benefits taxable and costs $222: 22.2%. From 2025 through 2028 the senior deduction of up to $6,000 a person shrinks by 6 cents for each dollar of income over $75,000 ($150,000 on a joint return), which adds to the rate in that range.
Credits that shrink as you earn more
The earned income credit grows with your first dollars of earnings, holds steady, then shrinks: by 15.98 cents a dollar with one child and 21.06 cents with two or more. A head of household with $32,000 of wages and two children is in the 10% bracket, and the child tax credit covers all of their income tax. Their earned income credit of $5,603 and the refundable child tax credit of $3,400 are larger than their taxes, so they get back $6,555. But their next $1,000 of wages costs $287.50, 28.75%: the credit shrinks by $211 and Social Security and Medicare take $76.50. A deduction from income doesn't help them: their child tax credit already cancels all of their income tax, its refundable part is already at its limit, and the earned income credit follows their earned income, which a deduction doesn't change.
The child tax credit shrinks by $50 for each $1,000 (or part of $1,000) of income over $200,000 ($400,000 on a joint return). Separately, its refundable part grows by 15 cents for each dollar of earnings over $2,500, up to the year's limit per child.
Gains stacked on top, and the 3.8% tax
Because long-term gains sit on top of ordinary income, more ordinary income can push them out of the 0% rate. With $50,000 of wages and $20,000 of long-term gains, a $1,000 withdrawal is taxed at your ordinary rate and also moves $1,000 of gains from 0% to 15%: $270, 27%. Above $200,000 of adjusted gross income ($250,000 joint, $125,000 separate), the 3.8% net investment income tax applies to the smaller of your investment income and the amount over.
Payroll tax limits
Social Security tax of 6.2% stops at the year's wage base, figured for each person; Medicare's 1.45% has no limit, and the 0.9% Additional Medicare Tax starts at $200,000 of wages ($250,000 for a couple, $125,000 separate). Self-employment tax is the employee's and the employer's share together, on 92.35% of profit, and half of it is deducted from income.
Assumptions and limits
- Federal taxes only. State and local income taxes are not included.
- Your whole return is figured twice, with and without your next amount, and the difference is what that amount costs.
- Social Security and Medicare are your share only, withheld from pay (6.2% up to the year's wage base, and 1.45%), or self-employment tax on your business profit. Your employer's matching share is not counted.
- The earned income credit is figured from the IRS's EIC Table rule for the year. It assumes everyone on the return has a valid Social Security number, lived in the United States more than half the year, is no one else's qualifying child and, without a qualifying child, cannot be claimed as anyone's dependent, and that each child counted meets the credit's tests. It is not figured on a separate return. A January 1 birthday 65 years earlier counts as 65 here for both the standard deduction and the credit (for the credit it is under 65), and a spouse who died during the year before turning 65 does not count as 65.
- The child tax credit assumes each child under 17 has a Social Security number and lived with you more than half the year. For three or more children, the second way of figuring the refundable part (Schedule 8812 Part II-B) is not used.
- On a separate return, Social Security is figured as if you lived with your spouse during the year: up to 85% of benefits is taxable from the first dollar of income. Head of household and qualifying surviving spouse are taken as you choose them; the calculator does not check for the qualifying person either status needs.
- Itemized deductions and adjustments are held at what you enter. Limits that change with income, such as the state and local tax cap's phase-down, the overall limit in the 37% bracket and IRA and student loan phase-outs, are not figured.
- Not included: the alternative minimum tax, the premium tax credit, education, saver's, dependent care, foreign tax and energy credits, the tips, overtime and car loan interest deductions, a spouse's self-employment income, capital losses and carryovers, collectibles and unrecaptured section 1250 gain (taxed at up to 28% and 25%), blindness, the limited standard deduction of someone claimed as a dependent, the earned income credit's rule for separated spouses, your employer's share of payroll tax, and state taxes. Medicare premium surcharges (IRMAA) and the Marketplace credit's 400% line are shown as thresholds, not priced.
- Self-employment: one business, yours, with no employees' wages and no qualified property for the qualified business income deduction. From 2026 the deduction is at least $400 when the business's qualified income is at least $1,000.
- Your next amount is added to this year's income, with everything else unchanged. The chart uses the rate schedule itself rather than the Tax Table, so its line is smooth; the answer above it follows the Tax Table, as the return does.
- The 2026 earned income credit follows the IRS's table rule on its published 2026 figures; the printed 2026 table is not out yet.
Input field details
What to enter in each box, where to find the number, and how this calculator treats it. When two calculators give different answers from the same numbers, it's usually because they handle one of these differently.
Filing status
The status you’ll file under for the year. It sets your brackets, your standard deduction and most of the income lines in the thresholds table.
Where to find itThe checkbox at the top of Form 1040; last year’s return as a guide.
How this tool treats itYour tax bracket is the rate on the last dollar of your taxable income: your income after adjustments, less the standard deduction (or your itemized deductions, if larger), the senior deduction and the qualified business income deduction. A qualifying surviving spouse uses the joint brackets.
65 or older
Tick for each person on the return who is 65 or older at the end of the year (born before January 2, 64 years earlier).
How this tool treats itIt raises the standard deduction, and from 2025 through 2028 adds a senior deduction of up to $6,000 a person that shrinks by 6% of income over $75,000 ($150,000 on a joint return). The senior deduction is not allowed on a separate return. Here 65 also ends the earned income credit’s age range; the one birthday where the two differ (January 1, 65 years earlier, which counts as 65 for the deduction but under 65 for the credit) is figured as 65 for both. A spouse who died during the year before turning 65 does not count as 65.
Children under 17
Children under 17 at the end of the year who lived with you more than half the year and have Social Security numbers.
How this tool treats itEach counts for the child tax credit and for the earned income credit. The earned income credit is figured from earned income (wages and self-employment earnings) and your adjusted gross income, and counts up to three children.
Allowed range0 to 10
Your income
Tick each kind of income you have this year, then enter the amounts. A kind left unticked counts as none.
Your wages
Your wages for the year as they appear in W-2 box 1, which already leaves out pre-tax retirement contributions and health, FSA and HSA payments from pay.
Where to find itForm W-2, box 1 (your last pay stub’s year-to-date federal taxable wages, plus the rest of the year).
How this tool treats itSocial Security tax is 6.2% of wages up to the year’s wage base, and Medicare tax 1.45% of all wages: your share only, figured for each person. Pre-tax 401(k), 403(b), 457(b) or TSP contributions go under More options, because Social Security and Medicare are owed on them; health, FSA and HSA payments from pay do not, because they are free of those taxes too.
Allowed range$0 to $10,000,000
Your spouse’s wages
Your spouse’s Form W-2, box 1, on a joint return.
How this tool treats itEach spouse has their own Social Security wage base. The 0.9% Additional Medicare Tax applies to a couple’s combined wages and self-employment earnings over $250,000 ($200,000 single, $125,000 separate).
Allowed range$0 to $10,000,000
Self-employment net profit
Your business’s profit for the year after expenses. A loss counts as $0 here.
Where to find itSchedule C, line 31 (or your bookkeeping’s profit for the year).
How this tool treats itSelf-employment tax is 15.3% of 92.35% of profit (12.4% of it only up to the wage base, less your wages), and half of it is deducted from income. The qualified business income deduction is figured for one business with no employees’ wages and no qualified property.
Allowed range$0 to $10,000,000
Not includedA spouse’s business.
Specified service business
Tick if your business is in health, law, accounting, actuarial science, performing arts, consulting, athletics, financial or brokerage services, or investing and trading.
How this tool treats itAbove a taxable income threshold, these businesses lose part or all of the qualified business income deduction.
Pensions, IRA and 401(k) withdrawals
The taxable amount of pensions, annuities, traditional IRA and 401(k) withdrawals, taxable Roth conversions and other ordinary income that is not wages or investment income.
Where to find itForm 1099-R, box 2a.
How this tool treats itTaxed at your ordinary rates; not investment income for the 3.8% tax or the earned income credit’s limit. A withdrawal before 59½ may also owe a 10% additional tax, which isn’t added here.
Allowed range$0 to $10,000,000
Social Security benefits
The whole year’s Social Security benefits, before Medicare premiums are taken out.
Where to find itForm SSA-1099, box 5.
How this tool treats itUp to 85% of benefits can be taxable, depending on your provisional income: your other income, tax-exempt interest and half your benefits. Each dollar of other income can make up to 85 cents of benefits taxable, which is why your next dollar can cost more than your bracket.
Allowed range$0 to $500,000
Interest, ordinary dividends and short-term gains
Taxable interest, dividends that are not qualified, and gains on investments held a year or less.
Where to find itForms 1099-INT box 1, 1099-DIV box 1a less box 1b, and 1099-B.
How this tool treats itTaxed at your ordinary rates. It is investment income: it counts toward the 3.8% net investment income tax above $200,000 of adjusted gross income ($250,000 joint, $125,000 separate) and toward the earned income credit’s investment-income limit.
Allowed range$0 to $10,000,000
Qualified dividends and long-term gains
Qualified dividends plus gains on investments held more than a year, less any long-term losses.
Where to find itForm 1099-DIV box 1b, and your long-term gains from Form 1099-B.
How this tool treats itTaxed at 0%, 15% or 20%, stacked on top of your other taxable income: ordinary income fills the brackets first, and these take the rate where they land.
Allowed range$0 to $10,000,000
Not includedCollectibles (taxed up to 28%) and net losses.
Your next dollar is
The kind of extra income to price: wages, self-employment profit, a pension or retirement withdrawal, interest, or a qualified dividend or long-term gain.
How this tool treats itEach kind moves different taxes and credits: wages add Social Security and Medicare, profit adds self-employment tax, investment income can trigger the 3.8% tax and the earned income credit’s limit, and every kind can make Social Security taxable or shrink a credit.
How much more
The extra income to price: a raise, a bonus, a withdrawal, a sale. The default is $1,000.
How this tool treats itYour whole federal return is figured with and without it; the difference divided by the amount is your true marginal rate. Your average rate is all your federal taxes (income tax after credits, plus Social Security and Medicare) divided by everything you received, and can be negative when refundable credits are larger.
Allowed range$100 to $1,000,000
Pre-tax retirement contributions from pay
What you (and your spouse) put into a 401(k), 403(b), 457(b) or TSP from pay before tax this year. Leave out Roth contributions.
Where to find itForm W-2, box 12, codes D (401(k)), E (403(b)) and G (457(b)), or your pay stub’s year-to-date contributions.
How this tool treats itThey are already out of box 1 wages, but Social Security and Medicare are still owed on them, so they are added back for those taxes only.
Allowed range$0 to $100,000
Tax-exempt interest
Interest from municipal bonds and other tax-exempt interest.
Where to find itForm 1099-INT, box 8.
How this tool treats itNot taxed itself, but it counts in provisional income for Social Security, toward the earned income credit’s investment-income limit, and in the income Medicare premiums and the Marketplace credit look at.
Allowed range$0 to $10,000,000
Adjustments to income
Deductions taken before adjusted gross income: a deductible traditional IRA contribution, HSA contributions made outside payroll, student loan interest, alimony paid under an older divorce.
Where to find itSchedule 1, Part II.
How this tool treats itHeld at what you enter. Your adjusted gross income is your income less these and half of self-employment tax.
Allowed range$0 to $1,000,000
Not includedThe income limits on IRA and student loan interest deductions.
Itemized deductions
Your total itemized deductions, if you itemize. The larger of this and the standard deduction is used.
Where to find itSchedule A, or last year’s as a guide.
How this tool treats itHeld at the amount you enter, whatever your income.
Allowed range$0 to $10,000,000
Not includedLimits that change with income: the state and local tax cap’s phase-down and the overall limit in the 37% bracket.
Children 17 or older who still count
Children who are 17 or 18, or full-time students under 24, or permanently disabled at any age, and lived with you more than half the year.
How this tool treats itEach is worth the $500 credit for other dependents (not the child tax credit, which is for children under 17) and counts for the earned income credit.
Allowed range0 to 10
Other dependents
Other people you claim as dependents, such as a parent you support.
How this tool treats itEach is worth the $500 credit for other dependents.
Allowed range0 to 10
Under 25
Tick for each person on the return who is under 25 at the end of the year.
How this tool treats itMatters only for the earned income credit without a qualifying child, which needs you, or on a joint return your spouse, to be 25 to 64 at the end of the year. It also needs that nobody else can claim you as a dependent, which is assumed here.
Marketplace health insurance
Tick if you buy health insurance through HealthCare.gov or your state’s Marketplace.
How this tool treats itFrom 2026, the premium tax credit ends when household income passes 400% of the poverty line. The thresholds table shows that line for your household; the credit itself isn’t figured here.
Questions
Does moving into a higher tax bracket mean all my income is taxed at the higher rate?
What is the difference between my tax bracket and my effective tax rate?
Why can my true marginal rate be higher than my bracket?
Can a raise ever leave me with less money?
Is a deduction or a credit worth more?
Which tax year should I choose?
Version history
- October 12, 2026 (version 1.0.0): First version: your federal bracket, average rate and the true marginal rate on your next dollar, with payroll tax, the earned income and child tax credits, Social Security and the senior deduction, for 2025 and 2026.