Chmod Calculator

Convert Linux file permissions between octal (755) and symbolic (rwxr-xr-x). Includes setuid, setgid and sticky bits.

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Symbolic rwxr-xr-x
Read (4)Write (2)Execute (1)
Owner
Group
Others
Special
chmod 755 file

How octal permissions work

Each digit is the sum of read (4), write (2) and execute (1) for owner, group and others. So 7 = 4+2+1 = rwx, 5 = 4+1 = r-x, 4 = r--. An optional leading digit sets special bits: setuid (4), setgid (2) and sticky (1) — e.g. 1777 is /tmp.

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