¿Qué hace HTML Formatter and Minifier?
HTML Formatter and Minifier permite formatear y validar datos directamente en el navegador y explica con claridad el resultado y sus límites. Capacidades verificadas: Prettier HTML formatting, Conservative HTML minification, Inline code left unchanged, Local HTML download.
Format, minify, and sanitize are different jobs
Use formatting for maintenance and review. Use minification only for a tested delivery artifact. Use a dedicated sanitizer when markup comes from an untrusted source; neither formatting nor minification makes HTML safe to render.
¿Cómo se utiliza?
- Choose Format HTML for readable markup or Minify HTML for a compact delivery copy.
- Paste an HTML document or fragment no larger than 2 MB into Input and select Convert.
- Review the output, especially whitespace-sensitive text and embedded code, then copy it or download html-output.html.
Ejemplo real de entrada y salida
Format and minify a compact document fragment
Entrada
<main><h1>KitLumi</h1><!-- remove --><p>Local tools</p></main>Salida
<main>
<h1>KitLumi</h1>
<!-- remove -->
<p>Local tools</p>
</main>
Minified: <main><h1>KitLumi</h1><p>Local tools</p></main>Format mode preserves the comment and lays out the markup. Minify mode removes the comment and collapses optional whitespace while retaining explicit tags and quoted attributes.
Errores frecuentes y soluciones
| Síntoma | Causa probable | Solución |
|---|---|---|
| The formatted structure is not the structure you expected. | HTML parsing is error-tolerant, so a missing closing tag or invalid nesting can be repaired according to HTML parsing rules. | Correct incomplete or misnested markup before treating the formatted result as an authoritative source. |
| The minified page behaves or renders differently. | Whitespace can be significant in inline content, preformatted text, templates, or code that reads exact text nodes. | Regression-test the output in its real template and browser context; keep the formatted source when whitespace semantics are uncertain. |
| Dangerous markup is still present after minification. | A minifier reduces source size; it does not sanitize scripts, event handlers, URLs, or embedded content. | Use a dedicated allowlist-based HTML sanitizer before rendering any untrusted HTML. |
Important behavior of HTML Formatter
Límite específico de esta herramienta: Minification is not sanitization: scripts, event handlers, unsafe URLs, and other active content remain in the output and must still be treated as untrusted.
Estándares y referencias de implementación
- Prettier browser documentation (opens in a new tab)Documents the standalone browser formatter and explicit HTML parser plugin used by Format HTML.
- html-minifier-terser official repository (opens in a new tab)Documents the HTML minification options and browser distributions used by Minify HTML.
- WHATWG HTML Standard (opens in a new tab)Defines HTML parsing, document structure, and whitespace behavior.
HTML Formatter — FAQ
Does the HTML Formatter upload my input?
No. Processing runs in the current browser tab, and the page does not send tool input to a KitLumi processing endpoint.
What input does the HTML Formatter accept?
It accepts one HTML document or fragment up to 2 MB. The workspace checks the input and reports malformed or unsupported values before it produces a result.
What does the HTML Formatter produce?
It produces Prettier-formatted HTML or conservatively minified HTML. Copy and download controls appear when the output format supports them.
What limitation should I know?
Minification is not sanitization: scripts, event handlers, unsafe URLs, and other active content remain in the output and must still be treated as untrusted.
¿Qué cambió?
Actualización material: HTML Formatter: Added Prettier HTML formatting, Conservative HTML minification, Inline code left unchanged, Local HTML download, responsive controls, explicit runtime disclosure, and task-specific examples and limitations.