{% tableofcontents "open" %}

Site Performance

Eleventy allows you full control over the output. That also means that by-default we do not include any costly runtime JavaScript bundles that often hamper site performance!

{% callout "", "md" %}Have a look at our new Partial Hydration <is-land> component!{% endcallout %}

Sites listed on the Eleventy Leaderboards are tested and ranked (approximately) monthly as a fun community way to maintain speedy site performance for Eleventy sites.

• Want to add your site to the Leaderboards?

{%- youtubeEmbed "b4frtsT4Cgo", "Full Control over HTML" -%} {%- youtubeEmbed "dIa2Y4zesnw", "Add your site to the Leaderboards (Weekly №6)" -%}

Looking for guidance on single page applications (SPA)?

Build Performance

Eleventy offers best-in-class build performance for JavaScript site generators.

Data taken from Which Generator Builds Markdown the Fastest? (July 2022).

Performance Tips

• You can analyze your project’s specific build performance metrics (via DEBUG or Node.js CPU Profiling).
• Memoize costly Shortcodes and Filters (we typically see the most expensive ones are those performing JavaScript, CSS, or HTML minification)
• Take passthrough copy out of your build-loop with the Eleventy Dev Server.
• Use the Image HTML Transform method to optimize images on-request during development.
• Use --incremental for Incremental builds.
• Use the Directory Output plugin to report per-template performance and file size information.
• Making network requests (to an API) can be expensive! Use the Fetch utility to create a local cache of external network requests (use duration to configure how long the cache should last).

{%- youtubeEmbed "KETQ4zS9Yp4", "28% build time performance improvement for Google’s web.dev (Weekly №1)", "30" -%} {%- youtubeEmbed "kUC87Zr0dKg", "Eleventy Build went from 54s to 17s—Pagination Memory/Performance Wins 🏆 (Weekly №10)", "344" -%} {%- youtubeEmbed "sfPNgt3joWI", "Markdown Benchmarks (Weekly №16)", "1566" -%}

Installation Performance

Data taken from The JavaScript Site Generator Review, 2023 (February 2023).