The 1.8.1 version of Rejex for Mac was available to download on the developer's website when we last checked. We cannot confirm if there is a free download of this app available.
Please check the Mac app with an antivirus before launch as it is downloaded from the developer's website, and we cannot ensure that it is safe. The actual developer of this free software for Mac is Ke Yang. Rejex for Mac is categorized as Productivity Tools.
From the developer:
Rejex is a light-weight application designed to help you learn, practice, and test regular expressions. The program offers immediate visual-match results for each regex pattern you enter. In addition, you can customize sample texts for a more accurate match test.
You may want to check out more Mac applications, such as pdf-DocPro or Pads X, which might be similar to Rejex.