grepWin is not available for Mac but there are some alternatives that runs on macOS with similar functionality. The best Mac alternative is DocFetcher, which is both free and Open Source. If that doesn't suit you, our users have ranked more than 25 alternatives to grepWin and seven of them are available for Mac so hopefully you can find a suitable replacement. Other interesting Mac alternatives to grepWin are grep (Free, Open Source), The Silver Searcher (Free, Open Source), FAR - Find And Replace (Free, Open Source) and Rummage (Free, Open Source).
DocFetcher is a portable German/English open source desktop search application. It allows you search the contents of documents on your computer. - You can think of it as Google for your local document repository.
Rummage is a cross platform tool for crawling directories and searching and replacing in text files. It is written in Python and uses wxPython for the GUI. Rummage allows for literal or regex searches and has configurations for limiting the files etc.
String Replacer for Mac allows to find and replace a list of strings inside files and folders directly or in batch mode. It allows to operate on multiple files using a multiple string couple replacement list. It works with just a single click or using drag and drop.