Free Concrete Slab Calculator Widget
The embedded Concrete Slab Calculator turns a slab's length, width and thickness into a bagged-mix count or a ready-mix cubic-yard order, plus an optional gravel sub-base and wire-mesh estimate and a materials cost range. Readers get the full plan inline. It fits any site whose visitors pour concrete: patio and hardscape contractors, shed, deck and garage builders, ready-mix and building-material suppliers, and DIY how-to publishers.
It's a single iframe — free, responsive, no registration, and it adds no link, ad or tracking script to your page.
Live preview
The embed adds no link, no ads and no tracking to your page. Prefer a guided version with a preview? Use the embed builder.
One small ask
Nothing links back to us from the widget itself. If your readers find it useful, please add a credit link to the Concrete Slab Calculator somewhere on your page — that's what keeps it free to maintain and helps others discover it.
Where the Concrete Slab Calculator widget fits
- A "how to pour a concrete slab" or "patio ideas" article
- A concrete or ready-mix supplier's product, mix or delivery page
- A shed, deck or garage build guide where a pad is step one
How to add it to your site
- Plain HTML: paste the snippet where you want the calculator to appear.
- WordPress: add a “Custom HTML” block and paste the snippet in. Avoid the “Paragraph” block — it strips iframes.
- Squarespace / Wix / Webflow: add an “Embed” or “Custom Code” / “HTML” element and paste the snippet.
- The second line (
embed.js) is optional — it just auto-sizes the frame height. You only need it once per page even with several calculators.
Sizing & responsiveness
Set the width to 100% to fill the column it sits in, or a fixed pixel value for a sidebar or narrow layout. Height is handled for you: with embed.js the frame grows and shrinks to fit the calculator (including after someone runs an estimate); without it, the frame stays at 900px and everything still works, just with an inner scrollbar on small screens.
Questions from site owners
Is it really free? Any catch?
Yes, free. No account, no API key, no usage limits, and no link, ads or tracking added to your page. The only thing asked is that, if the tool is useful to your readers, you add a plain credit link back to the calculator somewhere on the page.
Will it slow my page down or track my visitors?
No. The calculator loads in an iframe so it never blocks your page, it ships no third-party ad or analytics scripts onto your site, and it sets no cookies on your visitors. The optional resizer script is a few KB and loads asynchronously.
Does it decide bags vs. ready-mix for me?
It shows both, and flags when a pour is large enough that ready-mix delivery is usually the better call (roughly one cubic yard and up), so the reader can see the trade-off rather than guess.
Can readers turn the gravel base or wire mesh off?
Yes — both are optional checkboxes in the embedded form, and the material list and cost estimate update accordingly.
Can I resize it or set a fixed width?
Yes. Choose a responsive (100%) or a fixed-pixel width when you copy the code; the height auto-fits the calculator, with a fixed fallback if the resizer script is blocked.
Just need to run the numbers yourself? Use the full Concrete Slab Calculator — it has the formulas, a worked example and an FAQ. Or see all embeddable calculators.