To build a custom rich text editor, start by using the contentEditable attribute on a div element and implement execCommand or the modern Input Events API for formatting actions. You can add a custom toolbar with buttons for bold, italic, links, and other formatting options. For production use, consider extending an existing library like ProseMirror, Tiptap, or Slate.js, which provide a solid foundation with plugin architectures. utilAZ offers a free online HTML editor you can use as a reference for your implementation.

An inline editor renders directly within the page DOM using a contentEditable div, meaning it shares styles and scripts with the parent page. An iframe editor loads the editing area inside a separate iframe element, providing style isolation and preventing CSS conflicts with the surrounding page. Inline editors offer better performance and easier integration, while iframe editors provide stronger content isolation for complex environments.

You can extract HTML content from a rich text editor by accessing the innerHTML property of the contentEditable container or using the editor's built-in API method for getting content. Most editor libraries provide a getHTML() or getContent() method that returns clean, formatted HTML output. utilAZ lets you view and copy the generated HTML source directly from the code view panel.

Popular choices include Tiptap and ProseMirror for Vue and React, Quill for lightweight needs, and CKEditor or TinyMCE for full-featured solutions across all frameworks. Each framework has dedicated wrapper packages that provide native component integration. utilAZ provides a free browser-based HTML editor that works independently of any framework and requires no installation.

You can limit character count by listening to input events on the editor and checking the text length using innerText or the editor API's getTextLength() method. When the limit is reached, prevent further input by blocking keydown events or trimming excess content. Most editor libraries also support plugins or configuration options that enforce maximum character limits with visual counters.