# Chmod Calculator - Linux File Permissions 755 / rwxr-xr-x Converter

> Free online chmod calculator: tick read, write and execute for owner, group and others to convert octal (755) and symbolic (rwxr-xr-x), with setuid and sticky.

- URL: https://qilingtools.com/en/chmod
- Category: Developer Tools (https://qilingtools.com/en/dev)
- Tags: [Developer](https://qilingtools.com/en/tags/dev), [DevOps](https://qilingtools.com/en/tags/devops)
- Last updated: 2026-10-26
- Price: Free, no sign-up
- Privacy: Runs locally in the browser; files are never uploaded

Deploying a site, setting up SSH keys or writing shell scripts all involve Linux file permissions, and it is easy to forget what 755 or 644 actually mean. Tick read (r=4), write (w=2) and execute (x=1) for the owner (u), group (g) and others (o) and the tool shows the octal number and the symbolic form you see in ls -l; you can also type 750 or rw-r----- to parse it the other way. SetUID, SetGID and the sticky bit (e.g. 4755, 1777) are supported, and ready-to-copy chmod commands are generated in both numeric and u=,g=,o= forms with optional -R. Thirteen common permission presets are listed with their typical use.

## How to use

1. Tick read, write and execute for each role, or type an octal or symbolic permission
2. Optionally set SetUID, SetGID or sticky, enter a file name and choose recursive
3. Copy the generated chmod command, or click a common preset

## Features

- Checkbox grid converts to octal and symbolic instantly
- Parse octal or rwx strings in reverse
- SetUID / SetGID / sticky bit support (s, S, t, T)
- chmod commands in numeric and u=,g=,o= forms
- Optional -R; file names with spaces are quoted
- Shows the ls -l representation
- 13 common presets with explanations
- Calculated locally, no upload

## FAQ

### What do 755 and 644 mean?

Each digit is read(4) + write(2) + execute(1), for owner, group and others in order. 755 = rwxr-xr-x: owner full, others read and execute, typical for directories and scripts. 644 = rw-r--r--: owner read/write, others read-only, typical for regular and web files.

### Why should I avoid 777?

777 lets any user on the system modify, delete or replace the file, and a 777 web directory is an easy target for injected scripts. Use 755 for directories and 644 for files, and fix ownership instead of opening permissions when something needs write access.

### What is the s in rwsr-xr-x?

s means SetUID (owner position) or SetGID (group position): the program runs as the file's owner or group, e.g. passwd is 4755. A capital S means the special bit is set without execute permission. t is the sticky bit, as on /tmp (1777).

### Is my data uploaded?

No. Everything runs locally in your browser with no network upload and is discarded when you close the page, so it is safe for internal or sensitive data.

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