Chmod Calculator

Calculate Linux/Unix file permissions in Octal notation (`755`, `644`, `777`) and Symbolic notation (`rwxr-xr-x`). Features interactive permission checkboxes for Owner, Group, and Public (Read `4`, Write `2`, Execute `1`) and generates ready-to-copy `chmod` terminal commands.

Why Use This Tool?

• Linux File Permission Auditing: Quickly determine correct octal numbers for file permissions (`644` for files, `755` for directories).
• Web Server Security Hardening: Fix `403 Forbidden` or permission denied errors on Nginx/Apache web servers.
• Special Bit Configuration: Configure SUID (`4000`), SGID (`2000`), and Sticky Bit (`1000`).

How to Use

1. Check or uncheck Read (r), Write (w), and Execute (x) boxes for Owner, Group, and Public.
2. View updated Octal Permission (e.g. `755`) and Symbolic Permission (e.g. `-rwxr-xr-x`).
3. Copy ready-to-paste `chmod 755 filename` terminal command.

Real Working Example

Input:

Owner: Read, Write, Execute (7) | Group: Read, Execute (5) | Public: Read, Execute (5)

Output Result:

Octal Notation: 755
Symbolic Notation: -rwxr-xr-x
Terminal Command: chmod 755 filename

Important Technical Details & Specifications

• Octal Bitmask Math: Read = 4, Write = 2, Execute = 1. Summed per group (Owner, Group, Public).
• Special Bits Support: Supports SUID (Set Owner User ID), SGID (Set Group ID), and Sticky Bit.
• Client-Side Engine: Instant bitwise calculation in local browser memory.

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