Chmod Permission Calculator
Convert Unix file permissions between symbolic (rwxr-xr--) and octal (754) with a live checkbox grid — runs 100% in your browser with no upload.
rwxr-xr-- chmod 754
🔒 Calculated in your browser — nothing is uploaded.
What this chmod calculator does
Unix and Linux file permissions can be written two ways: as a nine-character symbolic string like rwxr-xr--, or as a three-digit octal number like 754. This tool converts between them live. Toggle the nine checkboxes for the owner, group, and others (each with read, write, and execute), or type an octal value, and the other side updates instantly. Each permission bit maps to a value — read is 4, write is 2, execute is 1 — and the three values for a role add up to one octal digit, so rwx is 7, r-x is 5, and r-- is 4. You can also set the special permission bits — setuid (4), setgid (2) and sticky (1) — which appear as a leading fourth octal digit (as in chmod 4755 for a setuid binary or chmod 1777 for a sticky /tmp) and as s, S, t or T in the execute slots.
How to read the result
The symbolic string is grouped in threes: the first three characters are the owner's permissions, the next three are the group's, and the last three are for everyone else. A letter means the permission is granted and a dash (-) means it is off. The tool also shows the matching chmod command so you can copy either the octal digits or the full symbolic string. Common values are 755 (rwxr-xr-x) for executables and folders, 644 (rw-r--r--) for regular files, and 700 (rwx------) for private files.
Frequently asked questions
How does 754 map to rwxr-xr--?
Split 754 into 7, 5, 4. Each digit is the sum of read (4), write (2), and execute (1): 7 = 4+2+1 = rwx for the owner, 5 = 4+1 = r-x for the group, and 4 = read only = r-- for others, giving rwxr-xr--.
What is the difference between symbolic and octal permissions?
They describe the same thing. Symbolic (rwxr-xr--) spells out each read, write, and execute bit as a letter or dash, while octal (754) compresses each group of three bits into a single 0–7 digit. chmod accepts either form.
Is anything I type uploaded to a server?
No. The conversion runs entirely in your browser with JavaScript. Nothing you type — the octal value or the checkboxes — is sent, stored, or uploaded anywhere.