chmod Calculator
Convert between numeric (755) and symbolic (rwxr-xr-x) Linux file permissions in both directions, and get the matching chmod command.
Toggle read/write/execute for owner, group, and others - or type in a numeric or symbolic value directly - this tool converts between all three representations instantly.
Owner
Group
Others
This tool also covers what's sometimes searched separately as a "Linux permission calculator", "file permission converter", or "octal permission calculator" - all three are the same underlying conversion, so they're combined here in one place instead of three near-identical pages.
What Is a chmod Calculator?
A chmod calculator converts between the three common ways Linux file permissions are represented: the numeric/octal form (like 755), the symbolic form (like rwxr-xr-x), and a plain checkbox view of what owner, group, and others can do - read, write, and execute.
Why Use This Tool?
The octal permission system is compact but not self-explanatory - remembering that 7 means read+write+execute, or working out what 644 means for a file's group, takes a moment for most people. This tool shows the breakdown instantly in both directions.
How to Use It
- Toggle read, write, and execute checkboxes for Owner, Group, and Others - or type a numeric value (e.g.
755) or symbolic value (e.g.rwxr-xr-x) directly. - The other two representations update automatically.
- Copy the resulting
chmodcommand to apply it in your terminal.
Understanding Octal Permission Digits
Each octal digit is a sum of read (4), write (2), and execute (1): 0 = ---, 1 = --x, 2 = -w-, 3 = -wx, 4 = r--, 5 = r-x, 6 = rw-, 7 = rwx. A permission like 755 is really three of these digits side by side, one each for owner, group, and others.
Common Permission Values
755 (rwxr-xr-x) is typical for directories and executable scripts - owner has full control, everyone else can read/execute but not modify. 644 (rw-r--r--) is typical for regular files - owner can edit, everyone else can only read. 700/600 restrict all access to the owner only, common for private keys and sensitive config files.
Limitations
This calculates the permission bits only - it does not execute chmod or change any real file. Special bits (setuid, setgid, sticky bit) are a separate, less commonly needed fourth digit not covered by this calculator.