Unix Permissions Calculator

Enter a numeric mode (750, 4755) or a symbolic mode (rwxr-x---), or just click the checkboxes — all three stay in sync. Computed via real bit math, the same approach used by this site's Shell Command Syntax Explainer for chmod. Runs entirely in your browser.

How setuid, setgid, and sticky show up symbolically

They fold into the execute position of the relevant triad instead of getting a character of their own: setuid replaces owner's x with s (or S if execute isn't also set), setgid does the same for group, and the sticky bit replaces other's x with t (or T) — exactly what ls -l shows. 4755 is rwsr-xr-x; 1777 is rwxrwxrwt.