MassageTXT is described as 'Convert between text and structured data' and is an website in the Development category. There are more than 10 alternatives to MassageTXT, not only websites but also apps for a variety of platforms, including Windows, Mac, Self-Hosted solutions and iPhone. The best alternative is RegExr, which is both free and Open Source. Other great sites and apps similar to MassageTXT are regular expressions 101 (Free), Expresso (Free), RegexBuddy (Paid) and iHateRegex (Free, Open Source).
Expressions is a minimal, distraction-free tool for experimenting with regular expressions. FEATURES - Minimalistic, non–distractive user interface. - Dark and light themes and full-screen mode. - Pattern syntax highlighting. - Pattern and text group highlighting.