Repair file without any paid software

If you’re trying to repair corrupted files on your Mac without paid software, start by using Disk Utility (Applications > Utilities > Disk Utility) and run First Aid on the drive where the file is stored—it can fix some directory-level issues.

For documents like Word or Excel, try opening them in Preview, TextEdit, or even Google Docs, which sometimes bypasses formatting errors. If it’s a system file, running sfc or fsck in macOS Recovery Mode can help. Also, Time Machine, if enabled, lets you restore a clean version. It won’t work for every case, but it’s your best shot with built-in tools.