How to Tell If a Website Is Built With Eleventy (11ty)
Eleventy (11ty) is a flexible, zero-JS-by-default static-site generator. Detect it via the generator meta tag reading 'Eleventy', its pure static HTML output and the absence of a framework runtime.
Eleventy — usually written 11ty — is a flexible, zero-JavaScript-by-default static-site generator beloved by developers who want simplicity, speed and full control. Because it is deliberately minimal, detecting it leans on the generator meta tag plus the static, runtime-free character of the output. This guide covers every reliable signal, why a minimalist SSG is detected differently, the look-alikes to rule out, and what an Eleventy build tells you about the developer.
What is Eleventy (11ty)?
Eleventy, first released in 2018, is a static-site generator written in JavaScript (Node.js) with a guiding philosophy of simplicity and flexibility. It takes content and templates and builds plain HTML at build time, but unlike more opinionated tools it imposes very little: it supports many templating languages (Nunjucks, Liquid, Handlebars, Markdown, plain JavaScript and more), does not dictate a CSS approach, and — crucially — ships zero client-side JavaScript by default. Any JS in the browser is whatever the developer deliberately adds. That minimalism makes Eleventy a favourite for blogs, documentation, portfolios, and performance-focused marketing sites built by developers who want a fast, lightweight result without a framework runtime.
For detection, the key context is that Eleventy is intentionally low-footprint: it produces pure static HTML with no framework runtime, and it does not impose a templating or styling fingerprint. So beyond its optional generator tag, an Eleventy site can look much like any other hand-built or statically generated page. Its presence signals a developer who values simplicity, speed and control — and a deliberately light client-side footprint, which usually correlates with excellent performance.
How Eleventy builds and serves pages
An Eleventy site is a set of pre-built static files generated at build time from content (often Markdown) and templates (in whichever language the developer chose). Eleventy can add a <meta name="generator" content="Eleventy v2.x.x"> tag to the head — the clearest detection signal — though whether it appears depends on the template and configuration, so it is not guaranteed. Because Eleventy ships no client-side runtime, the resulting pages are complete HTML on first load, with no hydration and no framework global, and typically a very small JavaScript footprint (only what the developer added).
Eleventy's flexibility is what makes it hard to fingerprint further: it does not enforce a directory structure, a CSS framework, or a templating syntax that survives into the output, so two Eleventy sites can look entirely different. The reliable signals are therefore the generator tag (when present) and the combination of pure-static, runtime-free, lightweight output (when it is not). Knowing this minimalism is itself the key to detection: you confirm with the tag, or you infer from the absence of any framework and the static nature of the site.
How to tell if a website uses Eleventy
Confirm the generator tag, or combine circumstantial signals if it is absent.
1. View the page source. Search the <head> for <meta name="generator" content="Eleventy ...">. This is the definitive signal and reveals the version when present.
2. Confirm static, runtime-free output. Check that the page is fully formed HTML on first load with no framework hydration, and confirm in the console that there is no React/Vue/Svelte global.
3. Note the light JS footprint. Eleventy ships no JS by default, so a static page with little or no JavaScript (only what the developer added) is consistent with Eleventy.
4. Look at hosting. Eleventy sites are commonly served from static hosts/CDNs (Netlify, Vercel, Cloudflare Pages, GitHub Pages), a supporting contextual signal.
5. Rule out other generators. If the generator tag is absent, check it is not declaring Hugo, Jekyll, Gatsby or Next; the absence of those, plus pure-static output, points toward a minimal SSG like Eleventy.
What the Eleventy signals look like
<head>
<meta name="generator" content="Eleventy v2.0.1">
</head>
<!-- Pure static HTML; zero framework runtime; minimal or no client-side JavaScript -->
The generator meta tag reading Eleventy is conclusive; absent it, the combination of pure static output, no framework runtime and a minimal JS footprint is indicative of a minimalist SSG such as Eleventy.
Eleventy versus other generators — avoiding false positives
Match the generator tag and runtime characteristics. Eleventy declares Eleventy; Hugo declares Hugo; Jekyll declares Jekyll; Gatsby (React) leaves a ___gatsby global and /page-data/ requests; Next.js leaves __NEXT_DATA__; Astro ships static HTML but may include hydration "islands" with astro-island elements. Among the pure, runtime-free static generators (Eleventy, Hugo, Jekyll), the generator tag is the main discriminator, since their output is otherwise similar. The biggest caveat is Eleventy's optional generator tag: when it is missing, you can confidently identify a minimal static generator but may not be able to prove it is Eleventy specifically without additional clues. Eleventy's zero-JS-by-default nature also distinguishes it from framework-based generators that hydrate.
How reliable is each Eleventy signal?
The <meta name="generator" content="Eleventy ..."> tag is definitive and reveals the version. The pure-static, runtime-free output with a minimal JS footprint is strong evidence of a minimalist SSG but not uniquely Eleventy on its own. Static-host deployment is contextual. The weakest situation — common with Eleventy given its minimalism — is a site with no generator tag, where you can identify a static generator but not definitively Eleventy. As a rule, seek the generator tag first; without it, treat the static, zero-JS signals as "minimal SSG, likely Eleventy" and corroborate with any other clues.
What an Eleventy build reveals about a developer
Finding Eleventy signals a developer who values simplicity, flexibility and performance. Choosing Eleventy is a deliberate, opinionated decision in favour of minimalism — full control over templating, no imposed framework, and zero client-side JavaScript by default — which appeals to developers who care about fast, lightweight sites and dislike heavy tooling. Eleventy is common on developer blogs, documentation, portfolios and performance-focused marketing sites, often maintained by a single developer or a small technical team via a Git-based workflow. Its presence tells you the site is built and published by someone hands-on and performance-minded. If you sell developer tooling, static hosting, or Jamstack services, an Eleventy site marks a technically capable, minimalist-leaning developer who appreciates lean tools — useful context for tailoring an approach.
What finding Eleventy means for sales, agencies and competitive research
For sales and prospecting, Eleventy marks a hands-on, performance-minded developer or small team — a fit for developer tools, static hosting, and Jamstack services aimed at people who value simplicity and control.
For agencies and consultants, finding Eleventy tells you the client runs a minimal, Git-based, zero-JS static workflow, so engagements can focus on performance, content workflow, search for static sites, or adding selective interactivity. It signals a developer-led, lightweight operation.
For competitive and market research, Eleventy adoption reveals a competitor's minimalist, performance-first approach. Spotting it suggests very fast pages and a developer-managed publishing process, useful when benchmarking site speed and noting who prioritises a light client-side footprint.
Eleventy in the wider stack
Eleventy sits at the build layer of a minimalist Jamstack stack. Content is typically Markdown in a Git repository, built by Eleventy and deployed to a static host/CDN (Netlify, Vercel, Cloudflare Pages, GitHub Pages) via a CI pipeline. Because Eleventy is unopinionated, the rest of the stack is whatever the developer chose: any CSS approach, optional vanilla JavaScript or a sprinkle of a small library for interactivity, privacy-friendly analytics, third-party forms, and client-side search. For an auditor, the valuable details are whether the generator tag confirms Eleventy and its version, the static host/CDN, how forms and search are handled, and the (usually minimal) client-side JavaScript; together these reveal a lean, developer-led static operation with Eleventy as the build tool.
A quick Eleventy confirmation walkthrough
Open the site and view the page source. Search the <head> for <meta name="generator" content="Eleventy ..."> — that confirms Eleventy and its version when present. Because the tag is optional, also confirm the page is pure static HTML on first load, check the console for the absence of any framework runtime global, and note the minimal JavaScript footprint. Check whether the site is served from a static host/CDN. The generator tag is enough to confirm Eleventy; without it, the static, zero-JS signals indicate a minimal static generator that is plausibly Eleventy.
A quick Eleventy detection checklist
- View source and search the head for
<meta name="generator" content="Eleventy ...">— conclusive when present. - Confirm pure static HTML with no framework hydration.
- Check the console for the absence of a React/Vue/Svelte runtime global.
- Note the minimal/zero client-side JavaScript footprint (zero-JS by default).
- Rule out Hugo/Jekyll/Gatsby/Next via their own generator tags or globals.
- Treat a missing generator tag as "minimal SSG, likely Eleventy" and corroborate.
Detecting Eleventy at scale
Checking one site is quick, but mapping static-generator adoption across many domains — to find minimalist, performance-first developers — calls for automation. StackOptic detects Eleventy (via its generator tag and output characteristics) and thousands of other technologies from a real browser. For related reading, see our guides to telling if a website is built with Gatsby and Astro, and the full Eleventy technology profile.
Frequently asked questions
What is the fastest way to tell if a site uses Eleventy?
View the page source and look for a generator meta tag: <meta name="generator" content="Eleventy v2.x">. Eleventy can add this tag, so it is the clearest signal when present. Because it is optional, also look for pure static HTML with no client-side framework runtime as supporting evidence.
Does Eleventy ship JavaScript to the browser?
Not by default. Eleventy is a zero-JS-by-default static-site generator: it outputs plain HTML, and any client-side JavaScript is whatever the developer chooses to add. So there is no Eleventy framework runtime or global in the browser; detection relies on the generator tag and the static, lightweight output.
Why is Eleventy sometimes hard to detect?
Eleventy is deliberately minimal and flexible — it does not impose a templating language, a CSS approach or any client runtime — so it leaves few fingerprints beyond the optional generator tag. If that tag is removed, an Eleventy site can look like any other hand-built or statically generated site, so you combine circumstantial signals.
How can I tell Eleventy from Hugo or Jekyll?
The generator meta tag names the tool: Eleventy declares 'Eleventy', Hugo declares 'Hugo', Jekyll declares 'Jekyll'. All three are pure static generators with no framework runtime, so the generator tag is the main discriminator. Without it, they are hard to tell apart from output alone.
What does it mean if a site is built with Eleventy?
Eleventy is a flexible, zero-JS-by-default static-site generator popular with developers who want simplicity and speed. Finding it signals a developer who chose a minimal, fast, static Jamstack approach with full control over templating and a deliberately light client-side footprint.
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