Free Calculator Widgets for Your Website
Add a working paycheck, overtime, or tip-tax calculator to your site with one line of code. Free, permanently. No ads inside the widget, no email capture on your readers, no signup, and no fee. Built for accountants, payroll firms, HR consultants, staffing agencies, and finance bloggers who want a real tool on the page instead of another block of text.
Why this exists
We build and maintain free U.S. tax and payroll calculators at SumFrog. Every figure is verified against IRS, SSA, and Department of Labor publications and updated when the law changes — the 2026 Social Security wage base, the new OBBBA tips and overtime deductions, and all 51 state and D.C. tax tables. Rather than let that work sit on one site, we make it embeddable. You get a tool your visitors actually use; we get our calculator in front of more people. That is the whole arrangement.
What you can embed
| Widget | What it does |
|---|---|
| State paycheck calculator (51 versions) | Take-home pay after federal tax, FICA, and that state's income tax, with 401(k) input. One per state — pick the one your audience lives in. |
| Overtime pay calculator | FLSA time-and-a-half and double-time, with the state daily-overtime rules noted. |
| No Tax on Overtime calculator | The 2025–2028 OBBBA deduction: 0.5× premium rule, $12,500 cap, MAGI phase-out. |
| No Tax on Tips calculator | The $25,000 qualified tips deduction with the Treasury occupation rules. |
| Employer payroll tax calculator | Employer-side cost per employee: matching FICA, FUTA, and your SUTA rate. |
How to embed (30 seconds)
Copy this into any page. Swap texas for any state slug, or use
a tool slug such as overtime-pay-calculator.
<iframe src="https://sumfrog.com/payroll/texas-paycheck-calculator/embed/"
width="100%" height="520"
style="border:1px solid #ddd;border-radius:10px"
title="Texas Paycheck Calculator (2026)"
loading="lazy"></iframe>That is the entire installation. No JavaScript to conflict with your theme, no tracking script, mobile responsive, and it inherits light or dark mode from the reader's device.
Terms, in plain English
- Free permanently. No fee now, no fee later, no upsell to your readers.
- No ads and no email capture inside the widget. Your visitors stay yours.
- Attribution: the standard widget carries one small "Calculator by SumFrog" line linking back to the source page. That link is how this stays free.
- Remove it any time, no notice needed. Delete the iframe and it's gone.
- We keep the data current. When the IRS or SSA changes a figure, your embedded widget updates automatically — you do nothing.
Want it without our branding?
We also produce white-label versions: your colors, your logo, no SumFrog attribution, and optionally a calculator built for your specific use case (industry-specific payroll, a client-facing quoting tool, or a state-and-locality combination we don't publish). That work is quoted per project. If you need a custom calculator embedded in a client portal or a marketing site, tell us what you need and we'll send a scope and a price.
Who this suits
Accounting and bookkeeping firms explaining payroll to clients. Payroll and PEO companies whose blog posts describe rules but can't show the number. HR consultants and staffing agencies. Restaurant and hospitality associations whose members are trying to understand the tips deduction. Personal finance writers who want a working tool instead of a static table.
Questions we get asked
Will it slow my page down? No. The widget loads lazily and is a few kilobytes of HTML and CSS with about 2 KB of JavaScript. There is no framework, no font download, and no third-party tracker.
Is the math reliable? Every calculator page lists its formula, a worked example, and links to the primary source — see our methodology page. Results are estimates and are labeled as such, not tax advice.
Can I see one working first? Yes — every calculator on this site is the same engine. Try the Texas paycheck calculator or the employer payroll tax calculator.
Do you need anything from me? No, but we'd like to know where it's running so we don't break your page with a future change. A one-line email is enough.