DiskWarrior - DiskWarrior, the world's most advanced and highest rated hard disk, hard drive, and disk repair and data recovery tool for macOS, OS X and Mac OS X.
Data Rescue - When Apple's system recovery fails, recover any and all files with Data Rescue 3. This data rescue software will even work if your Mac's hard drive fails to mount.
DriveDx - DriveDx is advanced drive health diagnostic and monitoring utility.
321Soft Data Recovery for Mac - The ultimate Mac Data Recovery software with RAID supported.
MiniTool Power Data Recovery - MiniTool Power Data Recovery is a freemium data recovery tool that works quite well considering the basic version is the only free aspect of the app.
ApowerRecover - Accidentally delete files and don't know what to do? Don't worry! ApowerRecover is an effective data recovery program that can help you get them back.