Beautify or minify HTML online. Auto-indents nested tags, formats attributes, and produces clean, readable output instantly — no installation.
HTML Formatter converts your data locally, without sending a single byte to a server.
It's one of the free
Format & Convert Tools
on UseToolSuite.
Use it below, then scroll down for a step-by-step guide, answers to common questions, and related tools.
What is HTML Formatter?
HTML Formatter is a free online tool that beautifies or minifies your
HTML code with a single click. It takes messy, unstructured, or
machine-generated HTML and reformats it with proper indentation and line
breaks, making it easy to read and maintain. Conversely, the minify
feature strips all unnecessary whitespace and line breaks to produce the
smallest possible output. All processing runs entirely in your browser —
your markup is never sent to any server, keeping your code private and
secure at all times.
When to use it?
Use the HTML Formatter when you receive minified or inline HTML from a
CMS, email template builder, or web scraper and need to understand its
structure. It's also helpful when preparing HTML snippets for
documentation, blog posts, or code reviews where readability matters.
The minify mode is ideal when you want to reduce page size and improve
load performance before deploying to production.
Common use cases
Front-end developers and designers commonly use HTML Formatter to clean
up auto-generated markup from WYSIWYG editors, inspect and debug email
template code, format embedded HTML snippets for technical tutorials,
and minify production-ready HTML for faster page loads. It's also used
by SEO specialists to review the structural hierarchy of web pages and
by QA engineers to compare HTML output between different builds or
environments.
HTML formatting standards: 2-space vs 4-space indentation
The HTML community is split on indentation width. Two-space indentation is favored by Google's HTML style guide, Airbnb, and most Prettier configurations because deeply nested HTML (which is common) quickly pushes content off-screen with wider indentation. Four-space indentation is preferred by developers who also work with Python and find 2-space nesting hard to scan visually. The most important rule is consistency within a project — configure your formatter once and enforce it with a pre-commit hook or CI check. This formatter lets you choose your preferred indent size and applies it consistently across your entire document.
Block-level elements (div, section, p, table rows) each start on their own line and increase the indent level for their children. Inline elements (a, span, strong, code) stay in the flow of their parent line, preserving the spacing semantics of inline content. Void elements like img, br, and input are never given closing tags, and boolean attributes (disabled, checked) are left bare — matching the HTML Living Standard rather than XHTML conventions.
If you work in a project with a build chain, Prettier or your IDE’s format-on-save should own HTML formatting — consistency comes from automation, not discipline. This tool covers everything outside that loop: HTML copied from a browser’s “View Source”, CMS template fields, email markup, scraped fragments, and generated output from tools that emit single-line HTML. Beautify here, inspect or edit, then paste back.
Minified HTML in production
HTML minification removes inter-tag whitespace and comments, typically saving 5–15% before compression. Two cautions: conditional comments and comment-based hooks (some frameworks and A/B-testing snippets target comments) must survive, so review what was stripped if a third-party script breaks; and don’t minify templates that still go through a server-side template engine — minify the final rendered output instead, at the edge or in the framework’s build step.
Debugging markup by re-indenting it
A surprisingly effective debugging technique: when a layout breaks because of an unclosed tag, beautify the page source and read the indentation. The first element whose indent level looks wrong — nested deeper than it should be — is almost always sitting inside the element that was never closed. The browser’s “Inspect Element” view shows the repaired DOM, which hides the mistake; formatted raw source shows what you actually wrote.
