An interactive calculator for Unix and Linux file/directory permissions. Select checkboxes, enter octal codes, or type symbolic notation to translate between standard file permissions and the corresponding chmod commands.
Special Bits
Translation & Representation
Terminal Commands
Plain-English Breakdown
- Owner: Calculating...
- Group: Calculating...
- Others: Calculating...
Key Features of Unix Permissions Calculator
- Octal to Symbolic Convert a 3-digit numeric permission to its full rwx string layout.
- Interactive Checkboxes Toggle permissions for Owner, Group, and Others to see updates instantly.
- chmod Command Generator Copy exact, ready-to-run shell commands representing your configurations.
Unix Permissions Calculator Examples
Convert Octal 755 to Symbolic
Evaluate the standard permission 755.
Input
755Output
Symbolic: -rwxr-xr-x. Owner: read/write/execute, Group: read/execute, Others: read/executeHow to Use Unix Permissions Calculator
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1. Toggle Permission Bits
Click the read, write, and execute checkboxes for Owner, Group, and Others to set the permissions.
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2. Watch Values Update Live
The octal notation, symbolic notation, and plain-English breakdown update on the fly.
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3. Copy the chmod Command
Click Copy next to the chmod command to use it directly in your terminal.
Common Use Cases for Unix Permissions Calculator
- Server Security Configurations Configure exact permission bits for critical config files or scripts.
- FTP Transfer Preparations Verify permissions requirements before pushing code to web directories.
- File Permission Debugging Troubleshoot 'Permission Denied' errors in automated Unix workflows.
The Technical Details
Bitmask mappings evaluate and format numeric octal inputs instantly.
Frequently Asked Questions
What is octal notation for file permissions?
Each permission set (Owner, Group, Others) maps to a digit 0-7: read=4, write=2, execute=1. Add them together. For example, rwx = 7, rw- = 6.
What are setuid, setgid, and sticky bits?
Special bits that modify execution behavior: setuid runs a file as the owner, setgid as the group, and the sticky bit restricts deletion in shared directories.
Is any data sent to a server?
No. All calculations run in your browser; nothing is ever uploaded.
What is the difference between chmod and chown?
chmod changes the permission bits of a file. chown changes the ownership (user and group) of a file.