Chmod Calculator
Tick the permissions you want or type 755, 644 or rwxr-xr-x and get the octal value, the symbolic form, ready-to-run chmod commands and a plain-English explanation.
Free · No sign-upHow to use Chmod Calculator
- 1. Tick read, write and execute for owner, group and others, or type a value like
755orrw-r--r--. - 2. Add setuid, setgid or the sticky bit if you need them.
- 3. Enter the file or folder name and choose recursive if needed.
- 4. Copy the chmod command in octal or symbolic form and check the plain-English summary.
Frequently asked questions
What does chmod 755 mean?
7 for the owner (read 4 + write 2 + execute 1), 5 for the group and 5 for others (read 4 + execute 1). The owner can do everything; everyone else can read and run the file or open the folder. It’s the usual mode for scripts and folders.
What does chmod 644 mean?
The owner can read and write (6) and everyone else can only read (4). It’s the standard mode for ordinary files such as web pages, images and configuration files.
How do I convert rwxr-xr-x to octal?
Split it into three groups — rwx, r-x, r-x — and add r = 4, w = 2, x = 1 in each: 7, 5, 5, so 755. Type it into the box above to convert any symbolic mode, including ones pasted from ls -l.
Is chmod 777 safe?
Rarely. 777 lets every user on the system modify or replace the file. It’s almost never the right fix for a “permission denied” error — change the owner with chown or add the user to the file’s group instead.
What are setuid, setgid and the sticky bit?
They form an optional fourth leading digit. setuid (4) runs a program with its owner’s rights, setgid (2) runs it with the group’s rights or makes new files in a folder inherit its group, and the sticky bit (1) stops users deleting each other’s files in shared folders like /tmp (1777).
What permissions should an SSH private key have?
600 (read and write for the owner only) or 400. SSH refuses to use a private key that other users can read, and ~/.ssh itself should be 700.