Chmod Calculator

Runs in browser

Generate Unix file permission commands visually

Quick Presets

Owner (User)

Group

Public (Others)

How to Use

Configure permissions using presets or checkboxes.

You will see:

  • Numeric Value (e.g. 755)
  • Symbolic String (e.g. -rwxr-xr-x)
  • Complete Command
  • One-click Copy
Generated Command
Numeric
644
Symbolic
-rw-r--r--
chmod 644 file

About Chmod Calculator

Unix file permissions control who can read, write, and execute files and directories. This calculator helps you visually construct the correct chmod command.

Understanding Permissions

Read (4)

View file contents. For directories: list contents.

Write (2)

Modify file contents. For directories: create/delete files.

Execute (1)

Run as program. For directories: enter with cd.

Common Permission Sets

Value Description
777 Everyone can read, write, execute (Insecure!)
755 Owner full, others read/execute (Scripts)
644 Owner read/write, others read only (Files)
600 Only owner can read/write (Secure configs)

⚠️ Security Best Practice

Avoid 777 on web servers — it gives write access to everyone. Use 755 for directories and 644 for files.