FileHint
JAEN

.html

Use caution

HyperText Markup Language

The source of a web page. A browser renders it; a text editor shows you the markup underneath.

MIME types

  • text/html

Category

web

Aliases

.htm

What opens this file

  • Any browser (Chrome / Edge / Firefox / Safari)
  • VS Code
  • Notepad / TextEdit

How to open by OS

Windows

  • Double-click opens in the default browser.

Mac

  • Double-click opens in Safari by default.

Linux

  • `xdg-open` launches the default browser.

Ios

  • Opens in Safari.

Android

  • Opens in Chrome.

Safety notes

  • HTML can execute arbitrary JavaScript. Phishing via local .html attachments that mimic login pages is widespread — check before opening.
  • Embedded file:// references can leak local resources when an HTML attachment runs.

Common mistakes

  • .htm and .html are the same format; the three-letter form survives from the MS-DOS 8.3 era.
  • Double-clicking local HTML files for development runs into file:// CORS restrictions — serve with something like http-server instead.

Related extensions

References