Chmod 644 - rw-r--r-- Permission Breakdown
Chmod 644 equals rw-r--r-- in symbolic notation. Owner read/write; group and others read-only. Use case: Public web files, HTML, CSS, and JavaScript assets. Toggle bits below, see security warnings, and copy chmod 644 commands for your path.
Permission bits
| Role | Read (r) | Write (w) | Execute (x) |
|---|---|---|---|
| Owner (u) | |||
| Group (g) | |||
| Others (o) |
Octal
644
Symbolic
rw-r--r--
Execute (x) lets the owner run this file as a program or script.
Commands
chmod 644 filenamechmod u=rw-,g=r--,o=r-- filenameCommon presets
How to run chmod 644
Check current permissions with ls -l path, apply chmod 644 path, then
verify again. Symbolic form: rw-r--r--
. Typical use: Public web files, HTML, CSS, and JavaScript assets.
ls -l your-file- note the current modechmod 644 your-file- apply this models -l your-file- confirm the change
chmod 644 bit breakdown
| Role | Octal digit | Symbolic |
|---|---|---|
| Owner | 6 | rw- |
| Group | 4 | r-- |
| Others | 4 | r-- |
Chmod 644 FAQ
What does chmod 644 mean?
Octal 644 maps to rw-r--r--. Owner read/write; group and others read-only. Typical use: Public web files, HTML, CSS, and JavaScript assets. Each digit encodes owner, group, and others permissions using read=4, write=2, execute=1, so you can rebuild the mode from individual rwx bits when auditing a deployment or fixing a broken upload script.
What is rw-r--r-- in octal?
Symbolic rw-r--r-- converts to octal 644. Owner digits come first, then group, then others. This page loads the calculator with 644 pre-selected so you can inspect or tweak individual bits and copy a ready chmod command for your path before you deploy.
When should I use chmod 644?
Public web files, HTML, CSS, and JavaScript assets Always verify against your deployment checklist and security policy before applying the mode recursively in production. Use the calculator above to preview symbolic notation and warnings, then copy the exact chmod command for your path.
How do I run chmod 644 in the terminal?
Execute chmod 644 path/to/file for a single file, or chmod 644 -R directory/ recursively. Confirm the path first - recursive chmod on the wrong folder is difficult to undo. Copy the command from the calculator output above, then re-run ls -l to confirm rw-r--r--.
Chmod 644 vs ls -l output: how do they relate?
ls -l shows symbolic permissions on the left (e.g., rw-r--r--) and may omit octal. This calculator bridges both views. 644 often appears on .html and .css files served by nginx or Apache. Match every rwx character before you ship.
Where is the full chmod calculator?
The main Chmod Calculator supports any 3-digit octal value and interactive rwx toggles with live security warnings. Visit /dev-tools/chmod-calculator/ for the complete tool with methodology, related modes, and Dev Tools cross-links when you need a mode outside this named preset page.
Sources & review
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