CHMOD Calculator: File and Folder Permissions

CHMOD Calculator — a convenient tool for setting access permissions. Enter a combination and get the result in both numeric and symbolic format.

PermissionOwner Rights(u)Group Rights(g)Others Rights(o)
read(4)
write(2)
execute(1)

Output Format

Special Permissions

Generated CHMOD Commands

Owner (u)
Group (g)
Others (o)
read
write
execute

Settings Reference

Verbosity Options

-vVerbose mode - display all changes made
-cChanges mode - display only changes made
-fSilent mode - suppress error messages
(default)Default mode - standard output

Special Permissions Options

-RRecursive - change permissions for directories and their contents
--preserve-rootPreserve root - fail to operate recursively on '/'
--reference=FILEReference file - use FILE's mode instead of MODE values
+sSetuid - set user ID on execution
+gSetgid - set group ID on execution
+tSticky bit - restrict deletion to file owner

Permission Types

r (4)Read permission (4) - allows reading the file
w (2)Write permission (2) - allows modifying the file
x (1)Execute permission (1) - allows executing the file
- (0)No permission (0) - denies access

User Groups

uUser (u) - file owner
gGroup (g) - file group
oOthers (o) - everyone else
aAll (a) - user, group, and others

Symbolic Notation

+Add permission (+) - adds the specified permission
-Remove permission (-) - removes the specified permission
=Set permission (=) - sets exact permissions
,Separator (,) - separates multiple permission changes

Common Examples

chmod 755 file.txtOwner: read/write/execute, Group: read/execute, Others: read/execute
chmod u+x file.txtAdd execute permission for owner only
chmod -R 644 directory/Recursively set read/write for owner, read for group and others
chmod --reference=ref.txt file.txtCopy permissions from reference file

CHMOD Calculator: Calculate File Permissions for Linux/Unix Systems

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The CHMOD calculator helps you calculate file and directory permissions for Linux and Unix systems. This tool converts between numeric (octal) and symbolic permission formats, making it easy to set the correct permissions for files and directories.

CHMOD permissions control who can read, write, and execute files or directories. The tool supports both three-digit octal notation (like 755) and symbolic notation (like rwxr-xr-x), providing flexibility for different use cases.

Perfect for system administrators, developers, and anyone working with Linux/Unix systems who needs to understand and set file permissions correctly.

Frequently Asked Questions (FAQ)

A chmod calculator is a tool that helps you calculate and understand Unix/Linux file permissions. It converts between numeric (octal) permission notation (like 755) and symbolic notation (like rwxr-xr-x), making it easier to set correct file permissions.

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Useful Instruments

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Numeric and Symbolic Permission Conversion

Convert between octal (numeric) and symbolic permission formats instantly. Enter 755 to see rwxr-xr-x, or vice versa.

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Visual Permission Representation

See a clear visual representation of permissions with checkboxes showing read, write, and execute permissions for each user type.

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User, Group, and Other Permissions

Set permissions for owner (user), group, and others separately, with support for all standard permission combinations.