👤 Your account

🎛 Build permissions by ticking boxes

Tick what each class of user may do — the octal code, symbolic string and the ready-to-paste chmod command update live. Or type an octal code below to see it decoded.

Special bits

Type an octal code instead (3 or 4 digits)

⭐ Common presets — and their security notes

The golden rule: least privilege. 777 (“everyone can do everything”) turns any small bug into a full compromise — it is almost never the answer, no matter what a forum post says.

🧩 The special bits, honestly explained

setuid (4xxx)The program runs with the file owner's rights, not the caller's. Essential for passwd/sudo; dangerous on anything writable or user-supplied.

setgid (2xxx)Programs run with the file's group; on a directory, new files inherit the directory's group — the standard trick for shared team folders.

sticky bit (1xxx)On a directory (like /tmp), only a file's owner may delete it, even though everyone can write. Shown as t in listings.

🗂 My Saved Scenarios

Permission setups you worked out for your servers and projects. Records live under your local account (or guest space) on this device — create, view, edit and delete them any time.

Chmod Calculator