Eleventy

Definition

Eleventy, also known as 11ty, is an open-source static site generator written in JavaScript that converts templates and content files into static HTML without requiring a client-side JavaScript framework. It is designed to be simple and unopinionated, supporting many template languages side by side within a single project and producing plain HTML output with no mandatory client-side hydration step or bundled framework runtime, unlike React- or Vue-based static site generators.

Overview

Eleventy was created as a reaction to the growing complexity of JavaScript-framework-based static site generators, aiming instead to be a straightforward tool that turns templates and data into HTML files, without requiring developers to adopt React, Vue, or any particular client-side framework. Its core promise is simplicity: point it at a directory of content and templates, and it outputs static HTML that can be hosted anywhere. Mechanically, Eleventy supports numerous templating languages simultaneously within one project, including Nunjucks, Liquid, Handlebars, Markdown, and plain JavaScript templates, letting teams mix formats as needed rather than committing to a single templating syntax. It reads data from JSON, JavaScript, or front-matter in content files, applies templates, and writes out static HTML, with no required client-side JavaScript runtime shipped to the browser unless a developer explicitly adds one. Among static site generators, Eleventy differs sharply from React or Vue-based generators like Gatsby, Nuxt, or Gridsome, which build a client-side single-page application on top of pre-rendered HTML. Eleventy instead produces output closer to traditional static HTML generation tools, prioritizing minimal shipped JavaScript and fast load times over rich client-side interactivity by default. In practice, Eleventy is used for blogs, documentation, marketing sites, and personal websites where developers want full control over output HTML and minimal JavaScript overhead, often paired with a lightweight amount of hand-written client-side script only where interactivity is truly needed. Its speed and simplicity have also made it a common choice for developer portfolios and open-source project sites, where contributors value being able to understand the entire build pipeline quickly. Its flexibility in templating languages also makes it attractive for teams migrating from older static site generators without wanting to rewrite all templates at once. The trade-off is that Eleventy provides less built-in structure for data fetching, client-side state, or complex interactive applications compared to framework-based generators, so teams building highly interactive sites often still reach for a JavaScript framework layered on top or choose a different tool altogether. Eleventy's minimalism is a deliberate choice that suits content-focused sites better than application-like experiences. Because Eleventy has no bundled client-side runtime, its output also tends to score well on page-speed and accessibility audits by default, before any additional optimization work is done. Because there is no single dominant templating convention enforced, teams with existing content in multiple formats can consolidate a migration onto Eleventy gradually, one template type at a time, rather than converting everything at once.

Key Features

• Static site generator producing plain HTML with no required client framework
• Supports multiple templating languages within a single project
• No mandatory client-side JavaScript or hydration step by default
• Reads content and data from Markdown, JSON, and front-matter
• Deliberately minimal and unopinionated core design
• Fast build times suited to content-heavy sites
• Flexible enough to mix templating syntaxes during migrations
• Popular for blogs, documentation, and marketing sites

Use Cases

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Frequently Asked Questions

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