Regex Group Extractor

What Can the Regex Group Extractor Do?

The Regex Group Extractor is a pure frontend online tool for visualizing regex match results and capture group contents. Enter a regex pattern and test text, and the tool automatically executes the match, displaying each match's full text and capture group values in a clear hierarchical structure. It supports named groups (?<name>) with name display, toggle for global/multiline/case-insensitive flags, and real-time match highlighting. All matching is done locally in your browser—no data is ever uploaded to any server.

Core Features

• Capture Group Visualization: Each match displayed as a card showing Group 0 (full match) and all capture group values
• Named Group Support: Automatically identifies (?<name>pattern) named groups, showing both group number and name
• Real-time Matching: Instant response on input—regex or text changes trigger automatic re-matching
• Flag Toggle: One-click toggle for g/i/m/s/u flags for different matching scenarios
• Multi-format Export: Export match results as JSON, CSV, or plain text

How to Use

Step 1: Enter a regex pattern in the input, e.g., (?<year>\d{4})-(?<month>\d{2}), and select desired flags.

Step 2: Enter test text in the text area, or click "Load Example".

Step 3: Click "Extract Groups" or press Ctrl+Enter to view each match's full text and group values.

Step 4: Click "Copy JSON" or "Copy CSV" to export results. Ctrl+Shift+C copies instantly.

Use Cases

Log Parsing

Use regex groups to extract timestamps, IPs, status codes, and other fields from logs for quick structuring of unstructured data.

Data Cleaning

Extract specific-format data from mixed text—emails, phone numbers, dates, URLs—and batch extract and export.

Regex Debugging

Verify that regex groups capture as expected, debug named groups and nested group match results.

Text Analysis

Extract specific patterns from text—variable names in code, HTML tag attributes, config file key-value pairs.

Technical Background

Regex capture groups are defined with (), numbered by left parenthesis order (Group 0 is the full match). Named groups (?<name>pattern) assign names accessible via match.groups.name. Non-capturing groups (?:pattern) group without capturing. Nested groups number from outer to inner, e.g., ((a)(b)) gives Group 1=ab, Group 2=a, Group 3=b. JavaScript's String.matchAll() returns an iterator of all matches, each containing a groups property for named groups.

FAQ