How do I convert chmod 755 to symbolic notation?

Type 755 in the octal field above — it converts to rwxr-xr-x instantly. Each octal digit maps to three bits: 7=rwx, 5=r-x, 4=r--. So 755 means owner rwx, group r-x, others r-x.

What do the numbers in chmod 644 mean?

Each digit is owner, group, others: 6 = read+write (4+2), 4 = read-only. So 644 gives the owner read/write and everyone else read-only — the standard for public files like HTML and images.

What is the difference between 755 and 644?

755 (rwxr-xr-x) adds the execute bit for everyone — needed for scripts and directories you want people to enter. 644 (rw-r--r--) has no execute bit — right for plain files. Use the calculator above to see both side by side.

What does rwxr-xr-x mean?

Read it in three groups of three: rwx (owner can read, write, execute), r-x (group can read and execute), r-x (others can read and execute). A dash means that permission is off.

Is chmod 777 dangerous?

Yes — 777 gives everyone read, write, AND execute, including the ability to modify or replace the file. It is occasionally needed for troubleshooting but should never be left on a public web server. Prefer 755 for executables and 644 for files.

Chmod Calculator — Octal & Symbolic Permissions Online

What is Chmod calculator?

Chmod Calculator — Free chmod calculator — tick Unix permission checkboxes or enter octal/symbolic modes to convert between 755, rwxr-xr-x and plain English. Runs in your browser.

Zero dependencies — original bit math written for this tool: each checkbox maps to its Unix bit value (owner r/w/x = 400/200/100, group = 040/020/010, other = 004/002/001); octal is the OR of the set bits, symbolic renders r/w/x per position. Reverse conversion parses octal digits 0–7 back into bits, and symbolic strings are validated against the strict rwxrwxrwx pattern. Special bits (setuid/setgid/sticky) are intentionally out of scope — this tool covers the standard 9 permission bits. Everything runs client-side; nothing is uploaded.

Why use this chmod calculator?

🎯

Built for chmod calculator

Free chmod calculator — tick Unix permission checkboxes or enter octal/symbolic modes to convert between 755, rwxr-xr-x and plain English. Runs in your browser.

📋

Transparent & honest

Covers the standard 9 permission bits only — setuid, setgid, and sticky bits are out of scope.

🔒

Private by design

Everything runs in your browser. Your inputs never leave your device.

📱

Works everywhere

Fully responsive — perfect on desktop, tablet, and mobile. No app needed.

🔄

Regularly updated

Regularly maintained and reviewed to ensure accuracy.

💡

Free forever

No accounts, no limits, no watermarks. Use Chmod Calculator as much as you need.

How to use Chmod Calculator

1Tick the nine permission checkboxes (read / write / execute for owner, group, and others) — or type an octal mode like 755, or a symbolic mode like rwxr-xr-x.
2Run the tool to convert between all three representations instantly.
3Read the octal output for your chmod command and the symbolic output to see exactly which bits are set.
4Copy the ready-made shell command (chmod 755 <file>) for your terminal.
5Read the plain-English description to confirm the permissions do what you intend before applying them.

What can you do with Chmod Calculator?

Chmod calculator online — Free chmod calculator — tick Unix permission checkboxes or enter octal/symbolic modes to convert between 755, rwxr-xr-x and plain English.
Linux permissions calculator — Free chmod calculator — tick Unix permission checkboxes or enter octal/symbolic modes to convert between 755, rwxr-xr-x and plain English.
Chmod 755 meaning — Free chmod calculator — tick Unix permission checkboxes or enter octal/symbolic modes to convert between 755, rwxr-xr-x and plain English.
Octal permissions — Free chmod calculator — tick Unix permission checkboxes or enter octal/symbolic modes to convert between 755, rwxr-xr-x and plain English.

Good to know

Covers the standard 9 permission bits only — setuid, setgid, and sticky bits are out of scope.
Descriptions assume standard Unix/Linux semantics; ACLs and SELinux contexts are not represented.
The tool computes modes; applying them (chmod) happens in your own terminal.

How it works

Zero dependencies — original bit math written for this tool: each checkbox maps to its Unix bit value (owner r/w/x = 400/200/100, group = 040/020/010, other = 004/002/001); octal is the OR of the set bits, symbolic renders r/w/x per position. Reverse conversion parses octal digits 0–7 back into bits, and symbolic strings are validated against the strict rwxrwxrwx pattern. Special bits (setuid/setgid/sticky) are intentionally out of scope — this tool covers the standard 9 permission bits. Everything runs client-side; nothing is uploaded.

Examples

Standard executable script

Status: ok — octal 755, symbolic rwxr-xr-x, the standard for scripts and public directories.

Octal input

Status: ok — symbolic rw-r--r--, the standard for public files.

Invalid octal rejected

Status: error — 8 is not an octal digit; modes use digits 0–7 only.

People also search for these — this tool handles them all:

chmod calculatorchmod calculator onlinelinux permissions calculatorchmod 755 meaningoctal permissions