Chmod Calculator
Work out the chmod number for the permissions you want — or see what a mode such as 644 or 4755 actually allows — with tick boxes for owner, group and others.
Result
Tick permissions or type a mode such as 755.
How to use this tool
- Tick read, write and execute for the owner, group and others, or type a mode such as
755orrw-r--r--. - The octal number, symbolic form and ready-to-use chmod commands update instantly.
- Special bits (setuid, setgid and sticky) are supported.
How it works
Each digit is the sum of read = 4, write = 2 and execute = 1, for the owner, the group and everyone else in that order. So 7 = 4 + 2 + 1 (rwx), 5 = 4 + 1 (r-x) and 4 = read only.
An optional leading digit sets the special bits: 4 = setuid, 2 = setgid, 1 = sticky. In symbolic form they appear as s or t in the execute positions.
Example
754
rwxr-xr--: the owner can read, write and execute; the group can read and execute; others can only read. Equivalent command: chmod u=rwx,g=rx,o=r filename.
Privacy and limitations
- Everything runs in your browser; nothing you paste is uploaded or stored.
- Typical choices: 644 for files and 755 for directories and scripts on web servers. Avoid 777 — it lets any user change the file.
Frequently asked questions
What does 755 mean?
The owner can read, write and execute; everyone else can read and execute. It is the usual mode for directories and scripts.
What does execute mean for a folder?
Permission to enter the folder and access files inside it. Read permission alone only lets you list the names.