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Chmod Calculator

Build Unix file permissions and read them as octal and symbolic notation.

GroupReadWriteExecute
owner
group
other
Octal
755
Symbolic
rwxr-xr-x
chmod 755 filename

Understanding chmod permissions

On Unix-like systems every file has three permission groups — owner, group, and other — each with read (4), write (2), and execute (1) bits. Summing the bits per group gives the familiar three-digit octal like 755 or 644, while the symbolic form rwxr-xr-x is what ls -l prints. It all computes in your browser.

Related tools: the decimal to octal converter, the base converter, and the ASCII table.

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