Symbolic Notation
----------(as shown by ls -l)----------
typeownergroupother
Permission Matrix
| Read(4) | Write(2) | Execute(1) | Octal | |
|---|---|---|---|---|
| Owner | - | - | - | 0 |
| Group | - | - | - | 0 |
| Other | - | - | - | 0 |
What Does chmod 000 Mean?
Owner can no access. Group can no access. Others can no access.
$ chmod 000 filenameCommon Use Cases
Locking a file completely — no one can read, write, or execute it. Used to temporarily disable access.
Security Notes
While this blocks all access, root can still read and modify the file. Use filesystem ACLs or immutable attributes for stronger protection.
Interactive Tool
Need to calculate a custom permission? Use the interactive permissions calculator to toggle individual bits and get instant results.
Unix Permissions Calculator