What does chmod 755 mean?

Chmod 755 grants the owner full Read, Write, and Execute rights (7), while group members and others can only Read and Execute (5). Commonly used for public directories and web scripts.

What does chmod 644 mean?

Chmod 644 allows the owner to Read and Write (6), and everyone else to only Read (4). This is the standard secure setting for normal web files and documents.

What are SetUID, SetGID, and the Sticky Bit?

SetUID (4000) runs an executable with file owner privileges. SetGID (2000) inherits group ownership. The Sticky Bit (1000) prevents users from deleting other users' files in shared folders like /tmp.

What does chmod 755 mean?

Chmod 755 grants the owner full Read, Write, and Execute rights (7), while group members and others can only Read and Execute (5). Commonly used for public directories and web scripts.

What does chmod 644 mean?

Chmod 644 allows the owner to Read and Write (6), and everyone else to only Read (4). This is the standard secure setting for normal web files and documents.

What are SetUID, SetGID, and the Sticky Bit?

SetUID (4000) runs an executable with file owner privileges. SetGID (2000) inherits group ownership. The Sticky Bit (1000) prevents users from deleting other users' files in shared folders like /tmp.

Free Linux / Unix Chmod Permissions Calculator

DeveloperOffline Ready · Zero Uploads

Calculate and convert Linux and Unix file access permissions. Toggle read, write, and execute bits across owner, group, and others with special SetUID, SetGID, and sticky bit support.

Loading Chmod Calculator sandbox...

Recommended Next Step

Continue your workflow with Number Base Converter (Binary, Hex, Octal, Decimal).

Open Next Tool

Frequently Asked Questions

developer

Number Base Converter (Binary, Hex, Octal, Decimal)

Convert numbers instantly between Decimal (10), Binary (2), Hexadecimal (16), Octal (8), and custom radices 2-36. 8-bit grouped bytes and BigInt support.

calculators

Scientific Calculator (Trigonometry, Log, Powers)

Perform advanced scientific calculations with trigonometry (sin, cos, tan), logarithms, square roots, factorials, and powers. DEG/RAD switch and history.

utilities

Universal Unit Converter

Convert between metric, imperial, and digital units: meters to feet, kg to lbs, Celsius to Fahrenheit, GB to MB, acres to square meters.