Regex Editor & Tester

This regex captures any text appearing after the marker '@20' and before one of the closing markers '@50', a period (.), 'F5', or 'AF5'. It uses a positive lookbehind for the opening code and a lazy dot-match with a lookahead for the terminators, making it ideal for extracting delimited content or fields between control codes in structured text, logs, or legacy system/terminal output.