Free Chmod Calculator
Set Unix file permissions visually by toggling read, write, and execute for owner, group, and others. See the numeric (octal) and symbolic notation in real time.
Unix Permissions Without the Guesswork
File permissions on Linux and macOS can be confusing. This visual calculator lets you check and uncheck permission boxes and instantly see the corresponding chmod command, octal value, and symbolic string.
Frequently Asked Questions
chmod (change mode) sets file permissions on Unix and Linux systems. It controls who can read, write, or execute a file.
755 means the owner can read, write, and execute (7), while group and others can read and execute but not write (5). This is a common permission for directories and scripts.
Numeric notation uses three octal digits (e.g., 644). Symbolic notation uses letters and operators (e.g., u=rw,g=r,o=r). Both achieve the same result.