Regex Tester & Validator

This regex matches a comma only when it is immediately followed by a non-whitespace character, ensuring it targets separators in compact CSV data rather than commas before spaces or line endings. It is useful for splitting or validating comma-separated values where fields are not padded with spaces, and for finding field boundaries in logs or data streams. The lookahead prevents consumption, making it ideal for use in split operations that require zero-width matching.