Regex Library - MerginIT e.U.

Regex

Email Address

Matches most common email address formats for basic input filtering.

Use this for a lightweight format check, not proof that an address exists or can receive mail.

Find

[a-zA-Z0-9._%+-]+@[a-zA-Z0-9.-]+\.[a-zA-Z]{2,}

Regex

Matches standard HTTP and HTTPS URLs in common text.

Useful for finding likely web URLs in text; use a URL parser when you need semantic validation.

Find

https?:\/\/(www\.)?[-a-zA-Z0-9@:%._\+~#=]{1,256}\.[a-zA-Z0-9()]{1,6}\b([-a-zA-Z0-9()@:%_\+.~#?&//=]*)

Regex

Matches a date in YYYY-MM-DD format.

Use this for the basic shape of an ISO calendar date, then parse it to verify that the day exists.

Find

^\d{4}-\d{2}-\d{2}$

Regex Replace recipe

Finds runs of non-alphanumeric characters so they can be replaced with hyphens.

Use with a lowercase transform and trim step to turn ordinary text into URL-friendly slugs.

Find

[^a-z0-9]+

Replace

Regex

Matches Markdown heading lines from level one through six.

Use this to find ATX-style Markdown headings in editors and content-processing scripts.

Find

^#{1,6}\s+.*$

Regex

Matches HTML-looking tags for simple text cleanup.

Use only for simple cleanup of trusted, predictable markup; use an HTML parser for real sanitization or transformation.

Find

<[^>]*>

Regex

Matches valid dotted-decimal IPv4 addresses such as 192.168.1.1.

Use word boundaries so the pattern finds addresses inside longer text without matching fragments of bigger numbers.

Find

\b(?:(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.){3}(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\b

Regex Replace recipe

Captures the entry type, citation key, and body of a BibTeX record to normalize or repair it.

Normalizes mixed brace and parenthesis entries into the standard @type{key, body} form with a find-and-replace.

Find

@(\w+)\s*[{(]([^,\s]+)\s*,([\s\S]*?)[})]

Replace

@$1{$2,$3}