How to Format HTML Online
Paste an HTML document or fragment, choose indentation and select Format HTML. The formatter uses Prettier's HTML parser locally and reports syntax it cannot understand. Copy the result or download a .html file. Input is limited to 200,000 characters for this browser interface. Keep the original when comparing output or editing markup generated by another system.
HTML Indentation and Nested Elements
Indentation exposes the relationship between containers and their children. A main element containing a heading, paragraph and list becomes easier to scan when nesting is consistent. Use the same spacing style across templates to make future diffs smaller. Browser error recovery and formatter parsing are different processes; markup that a browser displays may still be rejected or normalized by a formatter.
Formatting Inline vs Block Elements
Whitespace around inline elements can affect displayed text. The formatter uses CSS-based whitespace sensitivity rather than inserting line breaks blindly between every tag. Preformatted text also needs special treatment. Custom CSS can change an element's display behavior, so compare the rendered page after formatting important templates. Embedded JavaScript and CSS formatting is disabled here; those blocks remain source rather than being executed.
HTML Formatter vs HTML Encoder
Formatting changes the readable layout of markup. HTML encoding replaces characters such as < and & with entities so they can be represented in text. Use HTML Encoder when displaying a code sample, and HTML Formatter when reviewing the source itself. Neither operation is a complete security sanitizer. Untrusted exported HTML may still contain scripts, event handlers or network-loading elements.
Common HTML Formatting Problems
Unclosed tags, malformed attributes and template syntax from another language can prevent formatting. Choose the appropriate template-aware tool when the source is JSX, a framework template or server-side markup. Do not repair structural errors by guessing if the template has production behavior. Formatting improves readability, while semantic HTML, accessibility, valid URLs and safe content require their own review.
Standards and references
Frequently asked questions
How do I beautify HTML code?
Paste HTML or open a local file, select indentation and press Format HTML. The formatted source can be copied or downloaded.
Does formatting change rendered output?
The formatter tries to preserve meaningful whitespace, but custom CSS and template processing can change the result. Review the rendered page before replacing production markup.
Can I minify HTML too?
No. This tool beautifies HTML. Minification needs separate rules for whitespace, comments and embedded languages.
What is the difference between formatting and HTML encoding?
Formatting controls markup layout. Encoding represents special characters as entities for use in text. Neither is a substitute for sanitizing untrusted HTML.
Is HTML uploaded?
No. The HTML parser and formatter run locally. Pasted markup is shown as text and is not executed.