Regex Tester & Validator

Matches whole words that begin and end with the same letter. The first letter is captured in a group, followed by zero or more letters, and then a backreference (\1) requires the word to end with that identical letter, anchored by word boundaries on both sides. Useful for linguistic analysis, finding words like 'area', 'high', or 'that' in text, with multiline mode for scanning multiple lines.