Embed a ThisCalc calculator on your site

One line of HTML. No API key. No cookies. Mobile-responsive.

Quick start

<script async src="https://thiscalc.com/embed.js?calc=mortgage"></script>

That's it. Drop the line where you want the calculator to appear. The widget mounts a sandboxed iframe and auto-resizes to the content.

With a target container

<div data-thiscalc="bmi" data-theme="light"></div>
<script async src="https://thiscalc.com/embed.js"></script>

No-JavaScript version (WordPress, Wix, Squarespace, Ghost)

Most hosted platforms strip <script> tags out of post and page bodies, so the snippets above will silently do nothing there. This version is plain HTML and works anywhere an embed or custom-HTML block is allowed. Swap mortgage for any slug in the list below.

<iframe src="https://thiscalc.com/embed/mortgage?embed=1"
        width="100%" height="720" style="border:0;display:block"
        title="Mortgage Calculator by ThisCalc" loading="lazy"></iframe>
<p style="font:13px system-ui;opacity:.75;text-align:right">Powered by
  <a href="https://thiscalc.com/calculators/mortgage">Mortgage Calculator</a>
</p>

The fixed height is the one trade-off: without JavaScript the frame cannot auto-resize, so pick a height that fits the calculator you chose. 720 pixels suits most of them.

Live preview — Mortgage Calculator

Supported calculators (34)

Finance

mortgage — Mortgage Calculator
loan — Loan Calculator
compound-interest — Compound Interest Calculator
auto-loan — Auto Loan Calculator
apr-calculator — APR Calculator
salary — Salary Calculator
paycheck — Take-Home Pay Calculator
retirement — Retirement Savings Calculator
savings — Savings Calculator
debt-to-income — Debt to Income Ratio Calculator
down-payment — Down Payment Calculator
investment-return — Investment Return Calculator
inflation — Inflation Calculator
net-worth — Net Worth Calculator
fire-calculator — FIRE Calculator
cd-calculator — CD Calculator
car-lease-vs-buy — Car Lease vs Buy Calculator
rent-vs-buy — Rent vs Buy Calculator
refinance-break-even — Refinance Break-Even Calculator
fuel-cost — Fuel Cost / Trip Calculator
gas-mileage — Gas Mileage Calculator
tax-estimator — Federal Tax Estimator
tip — Tip Calculator
currency-converter — Currency Converter

Health & fitness

bmi — BMI Calculator
calorie — Calorie Calculator
body-fat — Body Fat Calculator
pregnancy-due-date — Pregnancy Due Date Calculator
macro-calculator — Macro Calculator
one-rep-max — One Rep Max Calculator
pace-calculator — Pace Calculator

Math & everyday

percentage — Percentage Calculator
average — Average Calculator
scientific — Scientific Calculator

34 calculators are embeddable today. Email hello@thiscalc.com to request another.

Options

Attribute	Default	Description
`data-thiscalc`	required	Calculator slug (e.g. `mortgage`).
`data-theme`	user pref	Force `light` or `dark`.
`data-height`	auto	Initial iframe height in px before auto-resize. Use `auto` or a number.

Privacy & performance

The iframe is sandbox="allow-scripts allow-same-origin allow-forms allow-popups" — no top-level navigation, no parent DOM access.
No tracking pixels on your page. We only see anonymous embed hits via our own analytics.
loading="lazy" — the calculator only loads when scrolled into view.
Auto-height via postMessage — never overflows or scrollbars.
Free forever. Self-hosted on Cloudflare's edge — sub-100ms loads worldwide.

Backlink (optional, appreciated)

Each embed includes a small "Powered by ThisCalc" attribution footer linking back to us. Keeping it helps us keep the embed free.