erusev/parsedown

Parsedown is a Markdown parser written in PHP. Markdown is a simple text format that uses characters like asterisks and hash marks to indicate things like bold text and headings; a parser turns that text into the equivalent HTML so it can be displayed on a web page. Parsedown's job is that conversion step, done from a PHP program. The README highlights a few practical traits. The whole library is one PHP file with no dependencies, which makes it easy to drop into a project. It supports GitHub flavored Markdown, the dialect used in README files on GitHub, and there is a separate extension called Parsedown Extra for the Markdown Extra dialect. The maintainer also claims it is fast and has automated tests. Installation is either through Composer, the standard PHP package manager, or by downloading the release and including the file directly. Using it from PHP is small: you create a Parsedown object and call its text method on a string of Markdown, and it returns the HTML. There is also a line method for parsing only inline markup such as emphasis without wrapping it in a paragraph. The README spends time on safety. If the Markdown comes from untrusted users, you switch on safe mode, and Parsedown will sanitize things like script-bearing link destinations. The maintainer still recommends layered defences, such as running output through a dedicated HTML sanitizer like HTML Purifier and setting a Content Security Policy in the browser. A separate setting escapes raw HTML, but the README warns this does not by itself prevent cross-site scripting. The library is used by Laravel, several PHP content management systems including Grav, Kirby, October, and Statamic, and by phpDocumentor.