Jeroen's Chmod Calculator Jeroen's Chmod calculator is the most robust calculator of its kind. It allows you to lookup and display the permission setting value (ie: 755) for files in 3 different ways, including its text equivalent (ie: -rwxr-xr-x). With this script you have all you could need to change your server files' permission! math related
Permissions:

owner group other
read
write
execute
Permissions:

owner group other
read
write
execute
NONE