Regex Text Extractor
Regex Text Extractor returns matches for a bounded, JavaScript-style regular expression.
Example: regex text extractor
a1 b2
1 2
How to use this tool
- Paste the text to search.
- Enter a supported pattern and optional flags.
- Inspect the extracted matches or the validation message.
Pattern and flags
This tool uses browser regular expressions with supported flags g, i, m, s, and u; global matching is applied for extraction. For instance, a pattern like “[A-Z]+” with the i flag can find alphabetic runs. Input is limited to 10,000 characters, patterns to 120 characters, and output to 1,000 matches.
Why some expressions are rejected
The implementation rejects several potentially expensive constructs, including backreferences, parentheses and alternation, and certain repeated wildcard forms. A pattern valid in a full regex engine can therefore be invalid here. Simplify the expression or use a dedicated regex environment when you need groups, alternation, or complex lookarounds.
Use extracted matches carefully
Matches show text matching the pattern; they are not proof that an email, URL, number, or other field is valid. Email Extractor and URL Extractor provide preset practical patterns for those two tasks. Check boundaries and false positives against the original text before treating extracted data as structured records.
Questions people ask
Can I use capture groups?
No; this bounded extractor rejects parentheses.
Does it replace matches?
No; use Find and Replace for literal substitutions.
How many matches can it return?
At most 1,000 matches from an accepted input.