chmod calculator
Tick the permissions or type an octal number; both stay in sync, with the symbolic form and the command alongside.
| read | write | execute | |
|---|---|---|---|
| user | |||
| group | |||
| other | |||
| special |
The ones you type from memory
| Octal | Symbolic | Typical use |
|---|---|---|
| 755 | rwxr-xr-x | directories, executables |
| 644 | rw-r--r-- | ordinary files |
| 600 | rw------- | private keys, secrets |
| 700 | rwx------ | private directories (~/.ssh) |
| 664 / 775 | rw-rw-r-- / rwxrwxr-x | group-writable projects |
| 1777 | rwxrwxrwt | /tmp (sticky: only owners delete) |
SSH is the strict one: ~/.ssh at 700, private keys at
600, authorized_keys at 600; anything looser and sshd
ignores them. And 777 is never the fix; it is how the problem moves
from "permission denied" to the incident channel.
Permissions drift; terminals fix them.
Moorfox gives you a real terminal on any managed machine, including headless Linux servers, so the wrong mode on a key file is a 10-second fix from the dashboard.