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,}Test, explain and share JavaScript regular expressions with live highlighting, then start from a practical pattern below. Every recipe lists its gotchas so you know when not to use it.
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[\w.+-]+ Repeats the previous token. Matches as many repetitions as possible, then backtracks.[\w.+-] Matches any one character in the set.\w Matches A–Z, a–z, 0–9 or underscore.. Matches "." (U+002E).+ Matches "+" (U+002B).- Matches "-" (U+002D).@ Matches "@" (U+0040).[\w-]+ Repeats the previous token. Matches as many repetitions as possible, then backtracks.[\w-] Matches any one character in the set.\w Matches A–Z, a–z, 0–9 or underscore.- Matches "-" (U+002D).(?:\.[\w-]+)* Repeats the previous token. Matches as many repetitions as possible, then backtracks.(?:\.[\w-]+) Groups tokens without creating a capture.\. Matches "." (U+002E).[\w-]+ Repeats the previous token. Matches as many repetitions as possible, then backtracks.[\w-] Matches any one character in the set.\w Matches A–Z, a–z, 0–9 or underscore.- Matches "-" (U+002D).\. Matches "." (U+002E).[a-z]{2,} Repeats the previous token. Matches as many repetitions as possible, then backtracks.[a-z] Matches any one character in the set.a-z Matches any character between the two code points, inclusive. (U+0061–U+007A). Case-insensitive.Practical regular expressions and find-and-replace recipes, shared with the site-wide reference data. Open any of them in the sandbox above.
Showing 8 of 8 patterns. Search and filters are shareable by URL.
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,}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()@:%_\+.~#?&//=]*)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}$Finds runs of non-alphanumeric characters so they can be replaced with hyphens.
Use with a lowercase transform and trim step to turn ordinary text into URL-friendly slugs.
Find
[^a-z0-9]+
Replace
-
Matches Markdown heading lines from level one through six.
Use this to find ATX-style Markdown headings in editors and content-processing scripts.
Find
^#{1,6}\s+.*$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
<[^>]*>
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]?)\bCaptures 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}