grepWin — The Complete Guide: Regex Search and Replace Across Thousands of Input Files
grepWin is a simple open-source Windows tool for searching and replacing text inside many files, with regular expression support. You launch it from the right-click menu on a folder. When you need to change a material coefficient in fifty input files of an analysis program, or find where a certain value appears across the whole project folder — this is the tool.
grepWin
Stefan Küng
Search and replace with regular expressions across thousands of text files — scripts, input files and config files.
Get it from the vendorWhat you get
- Search and replace in many files — in one operation.
- Regular expressions — match by pattern, not just by word.
- Filtering — by file type and size.
- Saved expressions — reuse helpful patterns.
- Open with a double-click — as in the file explorer.
Safety tip
Before a bulk replace, run a search only and review the list of matches. It is best to work on a copy of the folder or in a folder tracked with Git, so you can compare and roll back. The tool requires Windows 10 22H2 or later.
Related tools
To edit the files themselves — Notepad++ or Kate. To compare a file before and after the replace — KDiff3.
Notepad++
Don Ho
A light text and code editor for Windows — input files for analysis programs, data files and scripts.
Get it from the vendorKate
KDE
An advanced text and code editor — syntax highlighting for about 400 languages, split views, a built-in terminal and smart completion.
Get it from the vendor
KDiff3
KDE
Compare and merge two or three files or folders — to reconcile changes to scripts, input files and configs.
Get it from the vendorEverything
voidtools
Instant file search by name across the whole PC — find the latest revision of a drawing buried in project folders.
Get it from the vendorThe bottom line
grepWin saves hours of opening files one by one. Open source and free for commercial use too.