How to Tell if a Website Is Built with BigCommerce

If you want to know whether a website is built with BigCommerce, the fastest answer is to open the DevTools Network tab, reload, and look at where the assets come from: BigCommerce stores serve their images, CSS and JavaScript from cdn11.bigcommerce.com (and sibling cdn*.bigcommerce.com hosts). That CDN host is close to conclusive on its own. You can confirm it two more ways — type window.BCData in the DevTools Console (BigCommerce storefronts expose that object), and search View Source for /stencil/, the path used by BigCommerce's modern theme engine. This guide walks through every signal, shows how to read each one, and explains how to tell BigCommerce apart from Shopify, the platform it most resembles.

It sits alongside the broader how to find out what ecommerce platform a website uses and the wider how to find out what technology a website uses.

What BigCommerce is, briefly

BigCommerce is a hosted, software-as-a-service ecommerce platform — the same broad category as Shopify. A merchant signs up, builds a store on BigCommerce's infrastructure, and the platform handles hosting, the storefront, the cart and the checkout. Because it is hosted and centrally operated, BigCommerce stores share a great deal of common plumbing: the same content-delivery network, the same theme engine, the same JavaScript storefront objects. That consistency is exactly what makes the platform identifiable from the outside. The current generation of BigCommerce themes runs on Stencil, the platform's Handlebars-based theme framework, which replaced the older Blueprint system and left its own recognisable traces. For detection purposes, the important consequence is that a standard BigCommerce storefront broadcasts several stable, platform-specific signals whether the merchant likes it or not.

Signal 1: the cdn11.bigcommerce.com asset host

The single most consistent BigCommerce fingerprint is the CDN host. BigCommerce serves storefront assets — product images, theme CSS, JavaScript bundles — from its own content-delivery network, with cdn11.bigcommerce.com being the host you will most often see, alongside other cdn*.bigcommerce.com variants. When you load a BigCommerce store and watch the Network tab, you will see a stream of requests to URLs like https://cdn11.bigcommerce.com/s-<storehash>/... for images and theme files. That s-<storehash> segment is the store's unique identifier on the platform. Seeing assets served from a bigcommerce.com CDN host is essentially definitive — it is not a host other platforms use, and it appears on virtually every BigCommerce storefront regardless of the custom domain in the address bar.

Signal 2: the /stencil/ theme paths and markup

The second strong signal comes from the theme engine. Stencil-based storefronts expose /stencil/ in their asset and theme paths, and the rendered HTML carries Stencil's template output. View the page source (Ctrl/Cmd + U) and search for stencil — you will frequently find it in the URLs of theme CSS and JavaScript, and in references to the theme's compiled assets. Stencil themes also tend to include predictable structural markup and data attributes generated by the framework. Finding /stencil/ paths together with the cdn11.bigcommerce.com host is a clean, two-signal confirmation: the CDN tells you it is BigCommerce, and the Stencil paths tell you it is running the current theme engine rather than a legacy setup. This is the same "two independent signals" discipline that makes CMS detection reliable.

Signal 3: the window.BCData JavaScript object

BigCommerce storefronts expose a JavaScript object called window.BCData that holds store and cart context — things like the current cart state and store configuration the theme needs at runtime. This makes for a fast, reliable Console check. Open DevTools (F12), go to the Console, and type:

window.BCData

On a BigCommerce storefront it returns an object (often containing a cart and other store data); on a non-BigCommerce site it is undefined. Because this object is part of how the storefront operates, it is present across BigCommerce themes and is hard to remove without breaking functionality. It is the BigCommerce equivalent of checking window.Shopify on a Shopify store — a single, structural JavaScript tell that names the platform in one line.

Signal 4: the checkout on checkout.bigcommerce.com

The checkout flow is another giveaway. BigCommerce's checkout typically runs on checkout.bigcommerce.com or on a store subdomain that resolves to BigCommerce's checkout infrastructure. If you add an item to the cart and proceed toward checkout, watch the address bar and the Network tab: a redirect to or requests from a checkout.bigcommerce.com host confirm the platform handles payment, exactly as you would expect from a hosted SaaS store. (You do not need to complete a purchase to observe this — the checkout page loading is enough.) Identifying the checkout host also sets up the related question of which payment processor the store uses, which you can pursue with how to find out what payment processor a website uses.

The signal table

Signal	Where to find it	What it means
cdn11.bigcommerce.com (and cdn*.bigcommerce.com) assets	Network tab, View Source	Standard BigCommerce CDN — strongest single signal
s-<storehash> in asset URLs	Network tab	The store's unique BigCommerce identifier
/stencil/ theme paths	View Source, Network tab	BigCommerce's Stencil theme engine in use
window.BCData object	DevTools Console	BigCommerce storefront context — definitive in one line
checkout.bigcommerce.com checkout	Address bar, Network tab	BigCommerce-hosted checkout
BigCommerce platform headers	Response headers	Corroborating hint (sometimes present)

Any one of the top four is a strong signal; two together confirm BigCommerce with confidence.

Method 1: the DevTools Network tab

The most thorough single method is the Network tab. Open DevTools (F12), select Network, and reload the page. Watch the asset requests as they stream in and look for the cdn11.bigcommerce.com host (or another cdn*.bigcommerce.com). Click one of those requests and you will see the full URL, including the s-<storehash> segment that uniquely identifies the store on BigCommerce. The Network tab is reliable because it shows what the browser actually fetches — the real asset hosts powering the page — rather than anything that could be statically faked. It is also where you will later spot the checkout requests if you proceed toward payment. This same Network-tab discipline is the backbone of checking what JavaScript libraries a website uses.

Method 2: View Source

For a quick static check, View Source works well. Open the page, press Ctrl/Cmd + U, and use the in-page find to search for bigcommerce.com and stencil. You will typically find the CDN host in the URLs of theme stylesheets, scripts and images, and /stencil/ in the theme asset paths. Because BigCommerce renders these references directly into the server-returned HTML, they are present before any JavaScript runs, which is why a static source view catches them. View Source is the fastest first pass: if you immediately see cdn11.bigcommerce.com and stencil in the markup, you have your answer without even opening the full DevTools panel.

Method 3: the DevTools Console

For a one-line confirmation, use the Console. Type window.BCData and read the result: an object means BigCommerce, undefined means it is not (or the object loads later, in which case re-run after the page settles). You can expand the returned object to see the cart and store context the storefront uses. This method is valuable precisely because it tests a runtime property of the storefront — something that exists because the page genuinely runs BigCommerce's theme code, not merely because a string appears in the HTML. Pairing the Console check with the Network host gives you both a structural and a behavioural signal pointing at the same platform.

BigCommerce versus Shopify: telling them apart

Because BigCommerce and Shopify occupy the same niche — hosted, full-service ecommerce platforms — they can look similar at a glance, and confusing the two is the most common mistake. The fingerprints, however, are distinct, and a quick comparison settles it every time.

Tell	BigCommerce	Shopify
Asset CDN host	cdn11.bigcommerce.com (s-<storehash> path)	cdn.shopify.com (often /cdn/shop/ path)
JavaScript context object	window.BCData	window.Shopify, Shopify.theme
Theme engine path	/stencil/	/cdn/shop/t/<n>/assets/ (Liquid themes)
Checkout host	checkout.bigcommerce.com	checkout.shopify.com / Shop Pay

So when you see a store that feels like a hosted platform, the deciding moves are: check the asset CDN host, and check the JavaScript object in the Console. cdn11.bigcommerce.com plus window.BCData means BigCommerce; cdn.shopify.com plus window.Shopify means Shopify. For the Shopify side of this comparison in full, see how to tell if a website is built with Shopify. The same logic extends to distinguishing both from open-source platforms like WooCommerce, which you would identify through WordPress and plugin signals instead.

A worked example

Suppose you are sizing up a competitor's online store. You open the homepage, launch DevTools and switch to the Network tab, then reload. Within a second or two you see product images and theme CSS loading from cdn11.bigcommerce.com/s-a1b2c3/... — the BigCommerce CDN, complete with a store hash. That alone is strong, but you confirm: in the Console you type window.BCData and get back an object containing a cart and store settings. View Source shows /stencil/ in the theme asset URLs, telling you it is a current Stencil theme. Finally you add an item to the cart, click through toward checkout, and the Network tab lights up with requests to checkout.bigcommerce.com. Every signal agrees: this is a BigCommerce store, running Stencil, with BigCommerce-hosted checkout. In about a minute you have not just the platform but the theme engine and the checkout architecture — a complete read of the commerce stack.

Why the platform matters

Knowing a store runs BigCommerce tells you more than a label. It implies a hosting and architecture model (fully hosted SaaS, with the merchant building on the platform rather than running their own servers), which has cost and maintenance consequences. It signals a likely budget and scale — BigCommerce is positioned at small-to-mid and larger merchants, so a store on it is usually a serious commercial operation rather than a hobby project. It frames the theme and customisation approach (Stencil themes, with the option of a headless build via BigCommerce's APIs). And it tells app makers, payment companies and agencies whether a prospect is on their platform of interest. For competitive research, vendor sales and project scoping alike, the platform is one of the most informative single facts about a store, and BigCommerce specifically points to an established, mid-market-and-up commerce setup.

How reliable is BigCommerce detection?

Very reliable. The cdn11.bigcommerce.com asset host, the window.BCData object and the /stencil/ theme paths are intrinsic to how BigCommerce storefronts are built and served, so they appear on the large majority of stores and are not used by unrelated platforms. The main thing to watch is a headless BigCommerce build, where a custom front end (perhaps a Next.js or other framework storefront) pulls data from BigCommerce's APIs while presenting its own markup — in that case the classic Stencil and CDN signals may be muted, though the checkout and underlying commerce calls can still betray the platform. For the overwhelming majority of standard storefronts, though, the CDN host plus the BCData object plus the Stencil paths let you state "this is BigCommerce" with genuine confidence.

The workflow

1. Open the Network tab and reload; look for assets from cdn11.bigcommerce.com (and the s-<storehash> path).
2. Open the Console and type window.BCData — an object confirms BigCommerce.
3. View Source and search for bigcommerce.com and /stencil/.
4. Proceed toward checkout and watch for checkout.bigcommerce.com.
5. Compare against Shopify — cdn11.bigcommerce.com + BCData is BigCommerce, cdn.shopify.com + Shopify.theme is Shopify.

Go deeper

• The platform question in full: how to find out what ecommerce platform a website uses.
• The closest comparison: how to tell if a website is built with Shopify.
• The whole stack: how to find out what technology a website uses.
• The payment layer: how to find out what payment processor a website uses.

Want the platform, theme and full commerce stack identified automatically? Analyse any store with StackOptic — free, no sign-up.