HTML Beautifier

An HTML beautifier, also called an HTML pretty printer, turns dense or compressed markup into readable source with consistent indentation, line breaks, and nested structure. It is useful for reviewing minified HTML, debugging template output, and preparing markup for code review.

Paste HTML into the input panel or open a local .html file, choose your indentation and line-wrap settings, then click Beautify HTML or enable Live mode. The beautified output, heading outline, and statistics update instantly in your browser — nothing is sent to a server.

The terms are often used interchangeably, but beautifier emphasises making compressed or unreadable source human-friendly, while formatter often refers to style normalisation and indentation tools. ToolsSonic provides both as separate dedicated pages with distinct SEO routes, but both share the same local-only processing approach.

Yes. The Indent selector supports 2, 3, and 4 spaces plus tabs. The same indent unit is applied consistently at every nesting level, making the output predictable for version-control diffs and team style guides.

Line wrapping breaks long text content across multiple lines when it exceeds a character limit. Choose no wrapping, or 80, 120, or 160 characters. Wrapping at 80 characters matches most terminal widths and code-review tools; 120 and 160 are common for wide-screen development environments.

Live mode re-beautifies the input automatically as you type, after a short debounce delay. Turn it on for immediate feedback during interactive editing. Turn it off when pasting large documents to avoid triggering multiple reformats before you finish.

Yes by default. The Preserve raw-text blocks option keeps the content of pre, textarea, script, and style elements exactly as written, so code indentation and user-visible text are not altered. Disabling it normalises whitespace inside those elements.

Three modes are available. Preserve inline keeps all attributes on the opening tag. Wrap long attrs splits them to new lines when their combined length exceeds 80 characters. One attribute per line always places each attribute on its own indented line — useful for templates with many data or ARIA attributes.

Yes. Standard HTML5 void elements including br, img, input, meta, link, hr, source, embed, and wbr are emitted without closing tags. The tool does not add spurious closing tags that would produce invalid markup.

Yes. After beautification, the Document Outline panel lists every H1 through H6 heading with colour-coded level badges and indentation offsets. This is useful for reviewing accessibility hierarchy and document structure before publishing.

The statistics panel reports input bytes, output bytes, element count, maximum nesting depth, comment count, and void element count. These help you understand document complexity and compare how different settings affect output size.

No. Beautification changes whitespace and layout for readability. Validation checks standards conformance, required attributes, element relationships, and nesting rules. Use a dedicated HTML validator when you need diagnostics rather than a pretty-printed view.

No. A beautifier expands markup with indentation and line breaks for human review. A minifier strips whitespace and comments to reduce file size for delivery. Use the beautifier for code review and the minifier for production optimisation.

Yes. The browser DOMParser accepts fragments, but may silently repair unclosed tags or normalise document structure. Review the output when working with partial templates, server-side directives, custom elements, or intentionally incomplete markup.

Yes. Open file reads a .html or .htm file using the browser FileReader API and beautifies it entirely in memory. The file is never sent to a server, so it is safe for internal documentation, proprietary templates, and confidential content.

Yes. Copy beautified places the output on the clipboard and Download .html saves a beautified.html file locally. No account or server-side storage is required for either action.

Yes. Enable the Sort attributes A–Z checkbox and every opening tag's attributes will be reordered alphabetically by attribute name. This is useful for standardising large templates before code review, reducing noisy diffs when attribute order varies between developers, and enforcing a consistent style in component libraries. The sort is applied during serialisation and does not alter any attribute values.

When Final newline is enabled (the default), the beautified output always ends with a single newline character. This is the conventional Unix behaviour for text files and prevents no-newline-at-end-of-file warnings in diff tools, Git, linters, and most code editors. Disabling it trims all trailing whitespace, which some legacy tools or email systems require.

Initial indent level sets how many additional indent units to prepend to the entire output. Level 0 (default) starts at the document root. Level 1 adds one extra indent, level 2 adds two, and so on. This is useful when you need to embed a beautified HTML fragment inside a template or component that already has existing indentation — the fragment will align visually with the surrounding code without manual adjustment.

Attribute order can be sorted alphabetically using the Sort attributes A–Z checkbox. Embedded CSS and JavaScript are not minified or reformatted — the beautifier focuses on HTML structure, indentation, and line breaking rather than re-processing the content of script and style blocks.

The tool is completely free with no account required. All processing runs locally in your browser using the native DOMParser API. No HTML is uploaded, sent to a server, stored in localStorage, or retained after you close the tab.

Use the Beautifier when your HTML arrived minified or squashed onto one line and you need it readable again. Use the Formatter when you are tidying indentation and nesting in code you maintain.