Chmod Calculator

Calculate Unix/Linux file permissions visually. Convert between symbolic and numeric notation instantly. 🔒 Dev Tool

	Read (r)	Write (w)	Execute (x)	Octal
👤 Owner				7
👥 Group				5
🌍 Others				4

Numeric 755

Symbolic rwxr-xr--

Command chmod 755 filename

Enter numeric:

Common Presets

📄 Need to extract data from PDF invoices? Try our Invoice PDF to CSV tool →

How permissions work

Read (4): View file contents or list directory
Write (2): Modify file or create/delete in directory
Execute (1): Run file as program or access directory
Each octal digit = sum of r(4) + w(2) + x(1) for that group
Example: 755 = Owner 7 (rwx), Group 5 (r-x), Others 5 (r-x)

What do the three permission groups mean?

Owner: The user who owns the file. Group: Users belonging to the file's group. Others: Everyone else. Permissions are checked in order — if you're the owner, only owner permissions apply, even if group or others have more access.

What are the most common permission settings?

644 — standard files (owner can edit, everyone can read). 755 — executable files and directories. 600 — private files like SSH keys. 777 — full access for everyone (use sparingly, security risk). 400 — read-only for owner (e.g. config files).

How do I use the chmod command?

Run chmod [permissions] [filename] in your terminal. For example: chmod 755 deploy.sh makes a script executable. To apply recursively to a directory: chmod -R 755 /path/to/dir. You can also use symbolic notation: chmod u+x file adds execute for owner.

Hash Generator UUID Generator Password Generator JWT Decoder Cron Generator Base64