Embed our calculators on your site
Writing about pediatric BMI, ideal weight or body proportions? Put the working calculator right inside your article. It is free, it takes one copy and paste, and there is nothing to sign up for.
The one condition
Keep the credit link visible. Under every embedded calculator there is a single discreet line — for example “BMI Calculator for Children — by calculatorsfit.com” — that links back to the full tool. That link is the whole payment. Do not hide it with CSS, do not strip it, do not add rel="nofollow" to it. Everything else is up to you: no attribution elsewhere on the page is required, and you do not need to ask permission first.
What the embedded version does — and does not — do
- No advertising. In embedded mode the advertising script is never injected, so no ad request leaves your page. This is not a cosmetic setting on our side; it is the reason the mode exists.
- No audience measurement. Our analytics tag is skipped too, so the frame sets no analytics cookie on your visitors and does not add a consent obligation to your site.
- Nothing typed is sent anywhere. The math runs in the visitor's browser, exactly as it does on our own page. No weight, height or age reaches a server.
- It will not compete with your page in search. The embedded address is marked
noindexand its canonical still points at our full page. - It resizes itself. The frame reports its own height so it never ends up with an inner scrollbar or a strip of empty space.
How to do it
- Pick a calculator from the table below and copy its snippet — or open the calculator itself and use the “Embed on your site” button next to the share buttons, which hands you the same code already filled in.
- Paste it into your article where you want the calculator to appear. In a block editor use a “custom HTML” / “code” block, not the visual editor.
- That is it. If your platform strips
<script>tags, paste only the<iframe>line — the calculator still works, it just keeps the fixed height instead of adjusting itself.
The snippet
This is the code for the pediatric BMI calculator. For another tool, change the address in src and in the iframe[src*=…] selector to match the row you picked.
<iframe src="https://www.calculatorsfit.com/en/bmi-children?embed=1" width="100%" height="620" style="border:1px solid #e5e7eb;border-radius:12px" title="BMI Calculator for Children" loading="lazy"></iframe>
<script>addEventListener("message",function(e){if(e.origin!=="https://www.calculatorsfit.com")return;if(e.data&&e.data.tipo==="altura-calculadora"){var f=document.querySelector('iframe[src*="/en/bmi-children"]');if(f)f.style.height=e.data.altura+"px";}});</script>
e.origin before it touches anything. Keep that check: it is what stops any other frame on your page from resizing ours — and it is the same discipline you should apply to every message listener you install.Calculators you can embed today
| Calculator | Language | Address to put in src | Suggested height |
|---|---|---|---|
| BMI Calculator for Children | English | /en/bmi-children?embed=1 | 620 |
| Ideal Body Proportions | English | /en/ideal-proportions?embed=1 | 620 |
| Calcolatore IMC bambini | Italian | /it/imc-bambini?embed=1 | 620 |
The interface of the embedded calculator is always in the language of the address you use, so an Italian article gets an Italian calculator. More tools and more languages are being added — if the one you need is not here yet, write to us and we will prioritise it.
🔢 What it looks like in practice
A parenting blog writes about growth charts and pastes the first snippet into the middle of the article. The reader types 8 years, 27.2 kg and 127 cm and sees a BMI of 16.9 at roughly the 50th percentile, without leaving the article. Under the result there is one grey line linking back to the full pediatric BMI calculator, where the reader can also see the LMS math, the CDC sources and the frequently asked questions.
Questions people ask
Is it really free?
Yes. There is no fee, no account and no key to request. The only condition is that the credit link shown under the calculator stays visible and stays a working link.
Will it show advertising on my site?
No. The embedded version loads no advertising script at all — no ad request is made. It also loads no audience measurement, so it sets no analytics cookie on your visitors.
Will the embed compete with my page in search results?
No. The embedded address carries a noindex directive and its canonical still points at our own full page, so search engines keep indexing your page, not the frame.
How does the frame get the right height?
The embedded page measures its own content and posts the height to your page with postMessage. The snippet includes a short listener that checks the sender origin and then sets the iframe height. Without the listener the frame still works, it just keeps the fixed height you set.
Can I change the look of it?
You control the frame: width, border, corner radius and margins are all yours in the style attribute. The inside of the calculator is not customisable, and that is deliberate — one appearance means one thing to maintain and no version of the tool that silently drifts out of date.
Can I embed it on a commercial site?
Yes, including on sites that carry their own advertising. The credit link condition is the same everywhere.
Will the address keep working?
These are the canonical addresses of the calculators and we intend to keep them. If one ever has to move, the old address will redirect.
Something is wrong with the embed. Who do I tell?
Write to contact@calculatorsfit.com with the address of the page you embedded it on. A broken embed on someone else's site is our problem to fix.