WinMerge: free tool to compare files and folders on Windows
WinMerge shows what changed between two files or folders. Its manual says it is free to use and open source under the GPL.
What it is
WinMerge is a Windows program that compares files and folders and shows the differences side by side. Its website calls it "an Open Source differencing and merging tool for Windows". It is a desktop program, not an AI tool and not a phone app.
Is it free?
Its manual says "We provide you with a good tool for free", and also says "WinMerge is not freeware (as many sites on the Web have stated): It is GPL licensed". So it is free to download and use, and the code is open source under the GPL. GitHub lists GPL-2.0. We saw no price and no sign-in step on the pages we read.
What you can compare, per the WinMerge site
- Text files, with the differences highlighted, even inside a line. Moved lines are detected.
- Two or three folders, with a list of the files that differ.
- Images, with differences highlighted or the pictures overlaid.
- CSV and TSV files, shown as a table.
- It can look inside archives through 7-Zip.
Good to know, per WinMerge
- Current version on the downloads page: 2.16.58.2, released 2026-08-27. Installers are listed for x64, ARM64 and x86, with a ZIP of the binaries as well.
- It supports Windows XP SP3 or newer for the 32-bit installer, and Windows 7 or newer for 64-bit.
- The manual says it can show binary files but "editing binary files with WinMerge can break the files".
Our advice
- It is handy for checking what changed between two versions of a document saved as text, or whether a backup folder matches the original.
- Do not edit binary files in it, as the manual warns. Keep a copy before you merge anything.
- Download it only from winmerge.org.
Privacy and data
- We read no privacy statement for the program and make no claim on what data it collects. The WinMerge website itself shows Google ad code on its pages, so expect ads on the site. We did not check the program itself.
India
- No region limit appears on the pages we read. We did not test it from India. There is no price to convert.
Frequently asked questions
Is WinMerge free?
Yes. It is free to use and open source under the GPL, per its manual.
Does it work on Mac?
The site describes it as a tool for Windows, and we saw no Mac version.
Can it compare folders?
Yes, two or three at a time, per the site.
Sources: winmerge.org, Downloads, Manual, GitHub. Checked 20 October 2026.
Independent guide, not affiliated.