Side by side
Altova DiffDog vs WinMerge
Both stand on file comparison software. Which one you can start free with, which one lets you read the code, and what each costs once you pay.
Free trial Windows
DiffDog covers file and directory comparisons as well as database work, with Enterprise Edition adding three-way merges and expanded database comparisons. Check the Word requirement and the edition-specific features before choosing between the two one-time plans.
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Free plan Windows
WinMerge covers file and folder comparisons as well as image and table differences, with patch creation and conflict resolution. It targets Windows, and its published warranty terms are as-is.
Visit WinMergeThe facts
| Altova DiffDog | WinMerge | |
|---|---|---|
| Free plan | A free trial | Yes |
| Open source | Not published | Not published |
| Runs on | Windows | Windows |
| Lowest paid plan | DiffDog 2026 Professional Edition: $189, paid once | Free or on request |
| Plans published | 2 | 1 |
| Maker | Not published | Not published |
| Website | altova.com | winmerge.io |
| On file comparison software | #17 of 33 | #13 of 33 |
Altova DiffDog: what it does well
- Compares files, folders, and database data
- Supports bidirectional merging and direct file editing
- Enterprise Edition adds three-way comparison
- Exports difference reports in three formats
- Offers a 30-day trial
What to know first
- Available on Windows
- Word comparison requires Microsoft Word 2003 or later
- No free plan
WinMerge: what it does well
- Free and open-source under GPLv2.
- Folder comparison supports three-way comparison.
- Can create three patch formats.
- Includes Windows Explorer integration and 7-Zip browsing.
- Stable releases include source archives and SHA-256 checksums.
What to know first
- Official builds target Windows only.
- 32-bit builds require Windows XP SP3 or newer.
- 64-bit builds require Windows 7 or newer.
- The software is provided without warranty.
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