chmod Permission Calculator
Tick the permissions or type a mode: octal (755, 4755) or symbolic (rwxr-xr-x, -rwsr-xr-x).
About the chmod Permission Calculator
The chmod Permission Calculator converts Linux file permissions between octal (755, 4755) and symbolic notation (rwxr-xr-x, rwsr-xr-x), explains what the owner, group and others can do, supports setuid, setgid and sticky bits, and prints the ready-to-run chmod command with your file name safely quoted. It also warns about risky modes such as 777.
How to use the chmod Permission Calculator
- Tick the permission boxes or type an octal or symbolic mode.
- Optionally enter the file or directory name.
- Click Calculate and copy the chmod command.
Frequently asked questions
What does the extra leading digit mean (for example 4755)?
The first digit holds special bits: 4 is setuid, 2 is setgid and 1 is the sticky bit. In symbolic form they appear as s or t in the execute position.
Which input formats are accepted?
Three or four octal digits (755, 0644, 1777), nine symbolic characters such as rwxr-xr-x (optionally with a leading file-type character), or a full command like chmod 600 secret.
Are my data stored when I use the chmod Permission Calculator?
The text you submit is processed in memory to produce the result and is not saved. Like any web server, Code Converter logs basic visit data (page, IP address and browser) but never the content you paste.
Is the chmod Permission Calculator free, and can I call it from a script?
It is free and needs no account or signup. The same tool is available as a REST endpoint at POST /api/chmod-calculator; see the API documentation for the fields and examples.