Chmod Calculator | How to use and interpret results
Compare owner, group and other-user read/write/execute bits in octal and symbolic form. This is a permissions notation exercise without a connection to your server.
- Runs in your browser
- Nothing is uploaded
- No signup; device limits apply
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How to use this tool
Toggle the nine ordinary permission checkboxes, or enter three octal digits or a nine-character symbolic mode. Review special mode bits separately from this ordinary-bit display.
Results and examples
644 represents owner read/write and read-only access for group and others: rw-r--r--. The output chmod 644 still needs a target path and a separate execution decision.
Worked example
644 represents owner read/write and read-only access for group and others: rw-r--r--. The output chmod 644 still needs a target path and a separate execution decision.
Limitations
- Only three ordinary octal digits are accepted; setuid, setgid, sticky and ACLs are outside this view.
- Producing a command string does not change server permissions.
Fields
| Field | Guidance and constraints |
|---|---|
| r (read) | Check the unit and format displayed beside this field. |
| w (write) | Check the unit and format displayed beside this field. |
| x (execute) | Check the unit and format displayed beside this field. |
| Octal (e.g. 755) | Check the unit and format displayed beside this field. |
| Symbolic (e.g. rwxr-xr-x) | Check the unit and format displayed beside this field. |
Data handling
Processing stays in the current browser tab; the site does not upload tool input for the calculation itself.
Sources
Frequently asked questions
What permissions does 644 describe?
644 represents owner read/write and read-only access for group and others: rw-r--r--. The output chmod 644 still needs a target path and a separate execution decision.
Will this modify files on my server?
Setuid, setgid, sticky bits and ACLs are outside the nine-bit view. Producing a command string does not change server permissions.
