Eleventy (abbreviated 11ty) is a static site generator, a software system for creating websites.

Eleventy uses a "static first" design philosophy, meaning that it specializes in creating HTML documents that do not need to be refreshed or updated each time they are viewed by a web browser.

[3]: 2  Leatherman says he derived the name "Eleventy" from a story told to him, by his grandmother, about his own childhood mispronunciation of the number eleven.

"[3]: 3  By combining 11ty with a JavaScript framework performing API integration, developers may form a Jamstack application.

[7]: 15–40 Eleventy includes a local web server for use during development, activated with the --serve flag.