Web server file: 644
Owner: rw- · Group: r-- · Others: r--
chmod 644 filename
Chmod Calculator
Calculate Unix file permissions visually and get the chmod octal and symbolic notation.
Owner (user)
7Group
5Others
5Octal
755
Symbolic
rwxr-xr-x
chmod 755 filenameWas this tool useful?
About this tool
Unix file permissions control who can read, write, and execute a file. The three groups — owner (user), group, and others — each get a three-bit permission set represented as a digit from 0 to 7.
chmod 755 is the most common permission for executables and directories: the owner can do anything, and everyone else can read and execute but not write. chmod 644 is the standard for files: owner can read and write, everyone else can only read.
How to use it
- Tick the Read, Write, and Execute checkboxes for each group.
- The octal value and symbolic notation update live.
- Copy the chmod command and paste it into your terminal.
- Or type an octal value like 755 directly in the bottom field to set the checkboxes.
Examples
Executable script: 755
Owner: rwx · Group: r-x · Others: r-x
chmod 755 filename
Common problems
- chmod: Operation not permitted.
- Only the file owner or root can change permissions. Run with sudo if you own the system but not that particular file.