free -h

Show RAM and swap usage in human-readable format

free -h shows total, used, free, and available memory. The 'available' column is what new processes can actually use. Watch it during memory leak incidents.

Example

$ free -h
              total  used  free  available
Mem:            7.7G  4.2G  1.1G      3.1G
Swap:           2.0G  512M  1.5G

Tip: Type it yourself in the terminal below - reading is not the same as doing.