Rex says
Money math without the spreadsheet headache. Plug in your numbers and I'll show you exactly where the dollars land.
Try a scenario
Click to load — tweak from there.Inputs
Result
Outcome
Refund expected
Estimated amount
$526
Tax you will owe
$12,514
Projected withholding
$13,040
Adjust per paycheck to break even
-$43.83
Positive means withhold more
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One click, a permanent link with your numbers baked in.
How to use this
- 1Enter annual gross income ($).
- 2Enter filing status.
- 3Enter federal tax withheld so far ($).
- 4Enter withheld per paycheck ($).
- 5Enter paychecks remaining this year.
- 6Enter tax credits ($).
- 7Read your outcome on the right — it updates as you type.
- 8Hit Share to keep the scenario or send it to someone.
About this calculator
Compares what you will have withheld by year end against what you will actually owe. A big refund is not a win — it is an interest-free loan to the government you could have kept in your own account.
Worked example
Using the values the calculator loads with:
Inputs
- Annual gross income: 95000 $
- Filing status: Single
- Federal tax withheld so far: 6800 $
- Withheld per paycheck: 520 $
- Paychecks remaining this year: 12
- Tax credits: 0 $
Results
- Outcome: Refund expected
- Estimated amount: $526.00
- Tax you will owe: $12,514.00
- Projected withholding: $13,040.00
- Adjust per paycheck to break even: -$43.83
What each field means
Inputs
- Annual gross income ($)
- The annual gross income used in the calculation, measured in $. Starts at 95000 $ so you have a working example on load.
- Filing status
- Pick the option that matches your situation — the maths changes per option. Choices: Single, Married filing jointly.
- Federal tax withheld so far ($)
- The federal tax withheld so far used in the calculation, measured in $. Starts at 6800 $ so you have a working example on load.
- Withheld per paycheck ($)
- The withheld per paycheck used in the calculation, measured in $. Starts at 520 $ so you have a working example on load.
- Paychecks remaining this year
- The paychecks remaining this year used in the calculation. Starts at 12 so you have a working example on load.
- Tax credits ($)
- The tax credits used in the calculation, measured in $. Starts at 0 $ so you have a working example on load.
Results
- Outcome
- Returned as a plain value and shown as the headline result. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Estimated amount
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Tax you will owe
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Projected withholding
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Adjust per paycheck to break even
- Positive means withhold more
FAQ
How does the w-4 withholding calculator work?
Compares what you will have withheld by year end against what you will actually owe. A big refund is not a win — it is an interest-free loan to the government you could have kept in your own account. The underlying maths is: Projected withholding = Withheld to date + (Per-period withholding × Periods remaining). Compared against projected tax owed.
What do I need to enter?
6 values: annual gross income, filing status, federal tax withheld so far, withheld per paycheck, paychecks remaining this year, and tax credits. Each field starts with a sensible default, so you can change one number at a time and watch the result move.
What does the outcome result mean?
It is returned as a plain value and updates live as you edit the inputs, so you can compare two or three versions of a scenario in a few seconds.
Is this calculator free, and do I need an account?
Yes, it's free, and no account is required. Nothing you type is stored on our servers — the maths runs entirely in your browser.
How accurate is the result?
It applies the standard formula exactly, so the arithmetic is precise. Results are estimates before tax, fees, and inflation unless an input explicitly covers them.
Who is this tool for?
It's built for anyone comparing money scenarios before committing — budgeting a payment, sanity-checking a quote, or seeing what a change in rate or term actually costs.
Accuracy and limitations
- Results are estimates before tax, fees, and inflation unless an input explicitly covers them.
- Rates are treated as fixed for the whole period — variable-rate products will drift from this projection.
- This is educational maths, not financial advice. Check anything contractual with the lender or your accountant.
Related tools
Cite this calculator
Writing about this topic? Grab a citation — every link helps keep these tools free.
RevenueLab. (2026). W-4 Withholding Calculator. Retrieved from https://www.revenuelab.fyi/toolbox/w4-withholding
<p>Source: <a href="https://www.revenuelab.fyi/toolbox/w4-withholding" target="_blank" rel="noopener">W-4 Withholding Calculator — RevenueLab</a> (2026).</p>
Source: [W-4 Withholding Calculator — RevenueLab](https://www.revenuelab.fyi/toolbox/w4-withholding) (2026).