Embed the calculator
Put a working tax comparison on your own page. Your readers type an income and immediately see what they would owe across the states you chose — computed from the same sourced, dated tables that power this site.
Free · no signup · no tracking
Build your snippet
Pick a year, up to 4 jurisdictions, and a starting income. Copy the snippet and paste it into your page where you want the calculator to appear.
Preview
Your snippet
What you are pasting
The snippet has three parts, and each earns its place:
- The iframe is the calculator. It works on its own — if your CMS strips scripts, as WordPress.com and Substack do, everything still functions at the fixed height you chose.
- The credit line is a plain link back to TaxMath. Please keep it: it is the whole reason we can offer this for free, and a link inside an iframe does not count for anything.
- The script is optional. It does one thing — resizes the frame to fit its contents, so you do not have to guess a height. Drop it and nothing breaks.
Options
Everything is set through the query string on the iframe URL, so you can hand-edit the snippet without coming back here.
| Parameter | Example | What it does |
|---|---|---|
year | 2022 · 2023 · 2024 · 2025 · 2026 | Tax year the figures are computed for. Defaults to the current year. |
states | CA,TX,FL | Comma-separated jurisdiction codes, up to function(){throw Error("Attempted to call MAX_EMBED_JURISDICTIONS() from the server but MAX_EMBED_JURISDICTIONS is on the client. It's not possible to invoke a client function from the server, it can only be rendered as a Component or passed to props of a Client Component.")}. Unknown codes are ignored. |
income | 85000 | Starting income. Readers can change it; this is just where it opens. |
ltg / stg | 15000 | Long-term and short-term capital gains. Shown beneath the income field when set. |
persona | p1 · p3 | Load one of our named taxpayers instead of raw figures, so your article and the widget describe the same person. |
sd | 1 · 0 | Apply the single-filer standard deduction. On by default. |
An unrecognized value is ignored rather than shown as an error, so a typo degrades to the default instead of breaking your page.
Sizing
With the script included, the frame measures itself and reports its height to your page, so it fits exactly at any width. Without it, the frame stays at the height attribute in the snippet — around 320px for two jurisdictions, roughly 40px more for each additional one.
The widget is designed for a 320–700px column and reflows on its own below that; you do not need a separate mobile snippet.
What your readers get
Federal and state income tax for a single filer across 51 US jurisdictions and 5 tax years, including capital gains treatment and each state’s standard deduction. Figures still marked provisional say so in the widget itself, because a number that might move should never look settled.
The calculator does not model filing status beyond single, most credits, local income taxes, or payroll taxes. The methodology page is explicit about what is in and what is out — it is worth a look before you build an argument on top of the numbers.
Privacy
Nothing your readers type leaves their browser. The calculation runs entirely client-side, there is no analytics or tracking script in the frame, and the fonts are served from our own domain rather than a third party. We never see an income figure, and neither does anyone else.
Terms, briefly
- Free to use on any site, commercial or not. No permission needed.
- Keep the TaxMath credit line visible.
- Do not present the figures as tax advice or as a filing-grade calculation — they are estimates, and the widget says so.
- We may fix bugs and correct tax data behind the URL you paste; we will not change what it does. Anything that would count as a behavior change ships at a new version instead.
Found a problem, or want a configuration this page does not offer? Write to us at feedback [at] taxmath.org.