Why you should not parse HTML with regex

Nested tags, comments, CDATA and malformed markup will defeat any pattern eventually — HTML is not a regular language.

Patterns use the syntax shared by PCRE / Python / JavaScript; engine differences are flagged in the cheatsheet where they matter. Test any pattern at regex101.com — and pick the matching engine.

# <[^>]+> is fine for a quick grep — it is NOT an HTML parser

Good to know

Use a real parser: BeautifulSoup (Python), cheerio (JS), or Go's x/net/html. A tag-spotting pattern is fine for a quick grep — it is not a parser.

Regex Cheatsheet one-page card — patterns that actually work — The full one-page card — Regex Cheatsheet. Get the complete cheatsheet on GitHub