AllToolsHQ

Professional Regex Tester & Pattern Builder

Test, debug, and validate regular expressions with real-time feedback

Regular Expression Pattern

//g

Test String

Matches (0)

Enter a pattern and test string to see matches

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Advanced Regex Development Features
Professional-grade tools for regex development, testing, and optimization
Live Pattern Matching
Real-time regex matching with instant visual feedback and highlighting as you type
Key Benefits:
  • Immediate validation
  • Visual match highlighting
  • Error detection
  • Performance monitoring
Capture Groups & References
Advanced group extraction with named groups, backreferences, and nested capture support
Key Benefits:
  • Named group extraction
  • Backreference validation
  • Group replacement
  • Nested group support
Performance Analytics
Real-time performance metrics including execution time and complexity analysis
Key Benefits:
  • Execution timing
  • Pattern complexity
  • Memory usage
  • Optimization suggestions
Multi-Language Support
Test patterns across JavaScript, Python, Go, and Java regex engines with syntax highlighting
Key Benefits:
  • Cross-platform testing
  • Language-specific features
  • Syntax validation
  • Code generation
Comprehensive Pattern Library
Extensive collection of tested patterns for common use cases with explanations
Key Benefits:
  • Pre-built patterns
  • Use case examples
  • Pattern explanations
  • Category organization
Find & Replace Testing
Test replacement patterns with group references and complex substitutions
Key Benefits:
  • Replacement preview
  • Group substitution
  • Pattern validation
  • Batch processing
File Processing
Upload and test patterns against large text files, logs, and datasets
Key Benefits:
  • Large file support
  • Batch processing
  • Result export
  • Performance optimization
Pattern Explanation
Interactive pattern breakdown with step-by-step explanation and syntax guidance
Key Benefits:
  • Pattern visualization
  • Syntax explanation
  • Learning resources
  • Debugging assistance
Advanced Configuration
Full flag support with customizable options for different regex engines and modes
Key Benefits:
  • All regex flags
  • Engine selection
  • Custom options
  • Profile saving
Comprehensive Pattern Library
Ready-to-use regex patterns for common development and data processing tasks
Email & Web Validation
Email Address
Form validation
^[a-zA-Z0-9._%+-]+@[a-zA-Z0-9.-]+\.[a-zA-Z]{2,}$
URL/Website
Link validation
^https?:\/\/(?:www\.)?[-a-zA-Z0-9@:%._\+~#=]{1,256}\.[a-zA-Z0-9()]{1,6}\b(?:[-a-zA-Z0-9()@:%_\+.~#?&=]*)$
Domain Name
Network configuration
^(?:[a-zA-Z0-9](?:[a-zA-Z0-9-]{0,61}[a-zA-Z0-9])?.)+[a-zA-Z]{2,}$
IP Address (IPv4)
Network validation
^(?:(?: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]?)$
Data Extraction & Parsing
Phone Numbers (US)
Contact extraction
\+?1?[-.(]?(\d{3})[-.)\s]?(\d{3})[-.]?(\d{4})
Credit Card Numbers
Payment processing
\b(?:4[0-9]{12}(?:[0-9]{3})?|5[1-5][0-9]{14}|3[47][0-9]{13}|3[0-9]{13}|6(?:011|5[0-9]{2})[0-9]{12})\b
Social Security Numbers
Document processing
\b\d{3}-?\d{2}-?\d{4}\b
Hashtags
Social media analysis
#[a-zA-Z0-9_]+
Date & Time Formats
MM/DD/YYYY
US date validation
^(0[1-9]|1[0-2])\/(0[1-9]|[12]\d|3[01])\/(19|20)\d{2}$
DD/MM/YYYY
European date format
^(0[1-9]|[12]\d|3[01])\/(0[1-9]|1[0-2])\/(19|20)\d{2}$
ISO Date (YYYY-MM-DD)
Standard date format
^(19|20)\d{2}-(0[1-9]|1[0-2])-(0[1-9]|[12]\d|3[01])$
Time (24-hour)
Time validation
^([01]\d|2[0-3]):([0-5]\d)(?::([0-5]\d))?$
Programming & Code
Variable Names
Code validation
^[a-zA-Z_$][a-zA-Z0-9_$]*$
Hex Colors
CSS validation
^#(?:[0-9a-fA-F]{3}){1,2}$
JSON Strings
Data parsing
"(?:[^"\\]|\\.)*"
Function Calls
Code analysis
\b\w+\s*\([^)]*\)
Enterprise Regex Use Cases
Real-world applications across industries and technical domains
Form Validation & User Input
Validate user inputs in web forms and applications
Common Patterns:
Email addressesPhone numbersPasswordsPostal codesCredit cards
Industries:
E-commerceBankingHealthcareGovernment
Complexity:Beginner to Intermediate
Data Extraction & Mining
Extract structured data from unstructured text sources
Common Patterns:
Log parsingCSV processingWeb scrapingDocument parsingAPI responses
Industries:
AnalyticsResearchFinanceMarketing
Complexity:Intermediate to Advanced
Content Processing & Analysis
Process and analyze text content for insights and transformations
Common Patterns:
Sentiment analysisKeyword extractionContent cleanupFormat conversion
Industries:
PublishingMediaSocial MediaContent Marketing
Complexity:Intermediate
Security & Compliance
Identify sensitive data and ensure compliance with regulations
Common Patterns:
PII detectionCredit card maskingSSN identificationGDPR compliance
Industries:
HealthcareFinanceLegalGovernment
Complexity:Advanced
Software Development
Code analysis, refactoring, and development tool integration
Common Patterns:
Code lintingVariable extractionImport analysisSyntax validation
Industries:
Software DevelopmentDevOpsQuality Assurance
Complexity:Intermediate to Advanced
Log Analysis & Monitoring
Parse and analyze system logs for monitoring and debugging
Common Patterns:
Error detectionPerformance metricsUser activitySecurity events
Industries:
IT OperationsCybersecuritySystem Administration
Complexity:Advanced
Regex Flags Reference Guide
Complete guide to regex flags and their practical applications
g
Global
Find all matches rather than stopping after the first match
/test/g finds all occurrences of "test"
Essential for finding multiple matches in text
i
Ignore Case
Perform case-insensitive matching
/Test/i matches "test", "TEST", "Test"
User input validation and flexible text search
m
Multiline
Make ^ and $ match line boundaries within the string
/^line/m matches lines starting with "line"
Processing multi-line text and documents
s
Dot All
Make . match any character including newlines
/start.*end/s spans across line breaks
Parsing structured text with line breaks
u
Unicode
Enable full Unicode matching support
/\p{L}/u matches any Unicode letter
International text and emoji processing
y
Sticky
Match only from the last match position
Successive matches must be adjacent
Tokenization and sequential parsing
Frequently Asked Questions
Common questions about regex testing and pattern development
What is a regex tester and how does it work?
A regex tester is a tool that allows you to test regular expression patterns against sample text in real-time. It shows matches, capture groups, and validates pattern syntax while providing immediate visual feedback to help debug and optimize your regular expressions.
Which regex flags should I use for different scenarios?
Use the global flag (g) to find all matches, ignore case flag (i) for case-insensitive matching, multiline flag (m) for multi-line text processing, and unicode flag (u) for international text. The choice depends on your specific use case and text processing requirements.
How do I extract data using capture groups in regex?
Capture groups are created using parentheses () in your regex pattern. Each group captures the matched text within that section. Named groups (?<name>pattern) provide more readable and maintainable code. Our tester shows all captured groups with their values and positions.
Is my data secure when using this regex tester?
Yes, all regex testing is performed locally in your browser. No patterns, test strings, or results are transmitted to our servers. This ensures complete privacy and security for sensitive data and proprietary patterns.
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