SJ Chmod Calculator is a free iOS app designed for system administrators, developers, and Linux/Unix users who need to quickly and accurately calculate, understand, and convert Unix file permissions.

With its clear and intuitive interface, the app makes it easy to switch between numeric and symbolic representations of file permissions.

SJ Chmod Calculator offers two simple methods to obtain or verify file or directory access rights.

First mode: Numeric code input (755, 644, 600, etc.)

The user enters a 3-digit chmod value. The app instantly displays:

– A permissions table (read, write, execute) for each category: User (owner), Group, Others
– The equivalent symbolic notation (e.g., rwxr-xr-x)

Second mode: Interactive table input

The user simply checks the boxes for read (R), write (W), and execute (X) for each category. The app automatically calculates:

– The corresponding numeric chmod value
– The Unix symbolic permission string

Key features:

– Instant conversion between numeric and symbolic notation
– Visual table of permissions by category (user, group, others)
– Intuitive interface, easy to use
– Free application

A practical tool for all Linux/Unix users

Whether you’re a developer, system administrator, student, or advanced user of Unix/Linux systems, SJ Chmod Calculator helps you manage file permissions quickly and effortlessly.