Regex Validator

The Regex Validator is a powerful tool designed for both beginners and experts to validate and understand regular expressions swiftly. By testing regex patterns against sample strings, users receive instant feedback and can visualize matches, making regex a more approachable and efficient process.

How to Use the Regex Validator

Step 1: Enter Your Regex Pattern

• Input your regex pattern in the RegEx Pattern field. Common examples include:
  • ^[a-z]+$ for matching lowercase letters
  • \d{3}-\d{2}-\d{4} for validating US social security numbers

Step 2: Set Your Regex Flags

• Select relevant flags from the dropdown:
  • g (global): Matches all occurrences, not just the first one.
  • i (case-insensitive): Makes the match ignore case.
  • m (multiline): Treats each line as a separate string for matching.

Step 3: Enter the Test String

• In the Test String textarea, input the text you want to check against your regex pattern.

Step 4: View Results

• The tool will automatically present:
  • A Pattern Breakdown section explaining your regex components.
  • A Results section highlighting all matches in your test string.

Example Usage

For example, entering:

• Pattern: ^\d{3}-\d{2}-\d{4}$
• Test String: 123-45-6789

The tool will highlight 123-45-6789, confirming a successful match.

Basic Regex Patterns

Here are some fundamental regex patterns that can help you get started:

• .: Matches any single character except a newline.
• ^abc: Matches any string that starts with “abc”.
• abc$: Matches any string that ends with “abc”.
• \d: Matches any digit (equivalent to [0-9]).
• \D: Matches any non-digit character.
• \w: Matches any word character (equivalent to [a-zA-Z0-9_]).
• \W: Matches any non-word character.
• *: Matches 0 or more occurrences of the preceding element.
• +: Matches 1 or more occurrences of the preceding element.
• {n}: Matches exactly n occurrences of the preceding element.
• {n,}: Matches n or more occurrences of the preceding element.
• {n,m}: Matches between n and m occurrences of the preceding element.
• |: Acts as a logical OR, matching either the preceding or following pattern.
• (...): Groups patterns together for applying operators.

These basic patterns serve as a foundation for building more complex regex expressions tailored to your specific needs.

Disclaimer: This post is for personal use, but I hope it can also help others. I'm sharing my thoughts and experiences here.

If you have any insights or feedback, please reach out!

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