How do I use this regex tester?

Enter your regex pattern in the pattern field, add the text you want to test against, and select regex flags (global, case-insensitive, multiline). The tool instantly highlights all matches, displays match details including capture groups, and shows the total match count. You can also use preset patterns for common DevOps use cases.

What regex flags are supported?

This regex tester supports all standard JavaScript regex flags: 'g' (global - find all matches), 'i' (case-insensitive matching), 'm' (multiline - ^ and $ match line boundaries), 's' (dotAll - dot matches newlines), and 'u' (unicode - full Unicode support).

What are capture groups in regex?

Capture groups are portions of your regex pattern enclosed in parentheses (). They allow you to extract specific parts of a match. For example, in the pattern '(\d{3})-(\d{4})', the first group captures 3 digits and the second captures 4 digits. Our tester displays all capture groups for each match.

Can I test regex patterns for IP addresses?

Yes, this tool includes preset patterns for both IPv4 and IPv6 addresses. The IPv4 pattern matches standard dotted-decimal notation (e.g., 192.168.1.1), while the IPv6 pattern handles full and compressed formats. You can also create custom patterns for CIDR notation.

How do I match email addresses with regex?

Our regex tester includes an email pattern preset that matches common email formats. While a perfect email regex is complex, the included pattern handles most valid email addresses. You can also customize the pattern based on your specific validation requirements.

What are common regex patterns for DevOps?

Common DevOps regex patterns include: IP addresses (IPv4/IPv6), AWS ARNs (arn:aws:service:region:account:resource), URLs and domains, log timestamps, container IDs, Kubernetes resource names, semantic versions, and UUIDs. Our tool provides presets for many of these patterns.

Is this regex tester free to use?

Yes, this regex tester is completely free with no registration, no ads, and no usage limits. All pattern matching is performed locally in your browser, ensuring your data remains private and secure.

regex

Regex Tester - Regular Expression Debugger

Test regular expressions with real-time matching and syntax highlighting. View capture groups, match counts, and use common DevOps patterns for IPs, URLs, AWS ARNs, and more. Free, fast, and runs entirely in your browser.

Regular Expression

//gm

Flags:GlobalCase InsensitiveMultiline

Common patterns:

Test String

Quick Reference

. any char\d digit\w word char\s whitespace* 0+ times+ 1+ times? 0-1 times^ start$ end[abc] char class() group| or

Regex Tester Features

Real-Time Matching

Instant pattern matching as you type
Syntax highlighting for matches
Match count display
Capture group extraction
Match position indicators

Regex Flags Support

Global (g) - Find all matches
Case-insensitive (i)
Multiline (m) mode
DotAll (s) mode
Unicode (u) support

DevOps Pattern Presets

IPv4 & IPv6 addresses
AWS ARN patterns
URL & domain matching
Email validation
UUID & timestamp patterns

How to Use This Regex Tester

Enter Your Pattern

Type your regex pattern or select from DevOps presets like IP, URL, or ARN patterns

Add Test Text

Paste or type the text you want to test your regex pattern against

View Matches

See highlighted matches, capture groups, and match details in real-time

Regex Syntax Quick Reference

Special Characters

. - Matches any single character
^ - Start of string/line
$ - End of string/line
\d - Any digit (0-9)
\w - Word character (a-z, A-Z, 0-9, _)
\s - Whitespace character

Quantifiers

* - Zero or more times
+ - One or more times
? - Zero or one time
{n} - Exactly n times
{n,m} - Between n and m times
[abc] - Character class (a, b, or c)

Frequently Asked Questions

A regex tester is a tool that allows you to write and test regular expressions (regex) against sample text in real-time. It highlights matches, shows capture groups, and helps you debug patterns before using them in your code. Our regex tester includes common DevOps patterns for IPs, URLs, AWS ARNs, and more.

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