All tools on ChmodTest
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ChmodTest (main tool)
Free, 100% client-side chmod calculator. Convert octal 0755 to rwxr-xr-x and back, keep setuid, setgid and sticky bits, apply symbolic changes like u+x,go-w, and work out umasks.
Umask Calculator
Turn a umask into the default file and directory modes it produces (022 gives 644 and 755), or find the umask for the directory mode you want. Runs in your browser.
chmod Symbolic Mode Calculator
See what chmod u+x,go-w, a=r or g=u does to a starting mode: the resulting octal and rwx string, with the umask and directory rules GNU chmod applies. Runs in your browser.
Looking for explanations rather than a tool? ChmodTest guides cover 2 worked examples and gotchas.
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