Regex Tools for Developers
Build and test regular expressions with our free browser-based regex tools. See matches highlighted in real-time, test against sample text, and debug complex patterns. Perfect for form validation, data parsing, and text processing.
Regex Tools (1 Tools)
What Are Regex Tools?
Regular expressions (regex) are one of the most powerful tools in a developer's arsenal. These pattern-matching expressions can validate email addresses, extract data from logs, find and replace text across codebases, and parse complex string formats. However, regex syntax can be cryptic and error-prone – a misplaced quantifier or forgotten escape character can produce unexpected results. Our regex tools provide real-time feedback as you build patterns, highlighting matches instantly and helping you understand exactly what your expression will capture. Whether you're writing form validation, parsing server logs, or building data extraction pipelines, these tools make regex development faster and more reliable.
Common Use Cases
Form Validation
Build and test patterns for email addresses, phone numbers, passwords, URLs, and other user input validation requirements.
Log Analysis
Create patterns to extract timestamps, error codes, IP addresses, and other data from application and server logs.
Data Extraction
Parse structured text like CSV with quoted fields, XML attributes, or custom formats. Extract specific data points from unstructured text.
Code Refactoring
Build search patterns for find-and-replace operations across codebases. Match function calls, variable names, or deprecated API usage.
Why Use Our Regex Tools?
- Real-time match highlighting as you type
- Test against multiple sample strings simultaneously
- Support for all standard regex flags (global, case-insensitive, multiline)
- See capture groups and match indices
- Works with JavaScript regex syntax (compatible with most languages)
Frequently Asked Questions
What is regex?
Regex (regular expressions) is a sequence of characters that defines a search pattern. It's used for pattern matching in strings – validating emails, finding/replacing text, parsing data, and more.
How do I test a regex pattern?
Enter your regex pattern and test string in our Regex Tester. Matches are highlighted in real-time as you type. You can also test with different flags (global, case-insensitive, multiline).
What are the most common regex patterns?
Common patterns include: email validation, phone numbers, URLs, dates, and alphanumeric strings. Check our regex cheatsheet in the Resources section for more examples.