Chmod Calculator — Free Online Tool

Use Chmod Calculator for free — visual linux file permissions calculator. This tool runs 100% in your browser with zero server uploads. Part of ZeroApiTools, a collection of 65+ free developer tools. No signup, no API keys, no data collection. Works offline.

ZeroApiTools' free Chmod Calculator is a visual Linux file permission calculator — toggle Read, Write, and Execute permissions for Owner, Group, and Others and instantly get the correct numeric chmod value (like `755` or `644`). No Linux knowledge required, no signup, runs in browser.

What is a Chmod Calculator?

A chmod calculator is an online tool that helps you calculate Linux file permission values without memorizing the numeric system. It translates visual checkboxes (r/w/x) into the correct octal number (0-7) for each permission group, ready to use in a `chmod` terminal command.

How to Use the Chmod Calculator on ZeroApiTools?

  1. Check or uncheck the Read (r), Write (w), and Execute (x) boxes for Owner, Group, and Others (Public).
  2. The numeric value (e.g., 755) and symbolic notation (e.g., `-rwxr-xr-x`) update instantly.
  3. Copy the chmod command (e.g., `chmod 755 filename`) and run it in your Linux/Unix terminal.

What does chmod 755 mean in Linux?

chmod 755 means: Owner has full read+write+execute (7), Group has read+execute (5), Others have read+execute (5). It's the standard permission for public web server files and scripts.

What is chmod 644 used for?

chmod 644 gives Owner read+write access (6) and Group/Others read-only access (4). It's the standard for web files like HTML, CSS, and configuration files that should not be executed.