Chmod Calculator
Convert Unix/Linux file permissions between octal notation (755), symbolic string (rwxr-xr-x), and checkboxes. Generate the ready-to-run chmod command instantly.
Chmod Calculator
Toggle checkboxes or type an octal/symbolic value — all fields update instantly.
| Read (r) | Write (w) | Execute (x) | Octal | |
|---|---|---|---|---|
| Owner (u) | 7 | |||
| Group (g) | 5 | |||
| Others (o) | 5 |
Permission meaning
Owner: read, write, execute · Group: read, execute · Others: read, execute
Your data stays in your browser — no data is sent to any server.
Understanding Unix file permissions
Every file and directory on a Unix/Linux system has three permission sets: Owner (the user who owns the file), Group (a named group of users), and Others (everyone else). Each set has three bits: Read (r = 4), Write (w = 2), and Execute (x = 1). The octal digit for each set is the sum of the active bits, so rwx = 7, r-x = 5, r-- = 4.
Common permission values
755 (rwxr-xr-x) is typical for executable files and directories — the owner can read, write, and execute; group and others can read and execute. 644 (rw-r--r--) is standard for regular files — owner can read and write, others can only read. 700 (rwx------) gives full access only to the owner, suitable for private scripts.
Why use Chmod Calculator online?
Chmod Calculator in the browser saves context switching: no CLI install, no fragile one-liners, and instant feedback for teammates who do not live in the terminal. It is ideal for debugging, demos, and quick checks during code review.
Tips for best results
Work with a sample payload first, then paste production data. Keep privacy in mind: prefer local browser processing for secrets, tokens, and customer data. Bookmark this page for faster access next time.
How to use
- Toggle the Read, Write, Execute checkboxes for Owner, Group, and Others.
- Or type an octal number (e.g. 755) into the Octal field.
- Or type a symbolic string (e.g. rwxr-xr-x) into the Symbolic field.
- Edit the filename in the command box, then copy the full chmod command.
- Review the output and use Copy to paste into your editor, ticket, or chat.
- Need another utility? Scroll to Related Tools below for Chmod Calculator companions on skybin.io.
- For a deeper walkthrough, read the linked Skybin blog article at the bottom of this page.
Online tool vs terminal
| Terminal / CLI | This tool |
|---|---|
| Install CLI tools or write a one-off script | Open the tool in your browser — no install |
| Look up flags in man pages or Stack Overflow | Paste input or upload files where supported |
| Repeat for each file format or edge case | Get instant visual feedback and copy buttons |
All processing runs in your browser — nothing is sent to any server.
Frequently Asked Questions
- What does chmod 777 mean?
- chmod 777 grants read, write, and execute permissions to everyone — the owner, group, and all other users. It is rarely appropriate for production files because it allows anyone on the system to modify or execute the file.
- What is the difference between octal and symbolic notation?
- Octal notation represents the three permission sets as digits (e.g. 755), where each digit is the sum of the active bits: read=4, write=2, execute=1. Symbolic notation spells it out as a 9-character string like rwxr-xr-x, where a dash (-) means the permission is not set.
- Do these permissions apply to Windows?
- No. chmod and octal permissions are a Unix/Linux/macOS concept. Windows uses Access Control Lists (ACLs) managed through icacls or File Properties. The tool is intended for Unix-based systems.
- What does the execute bit mean for a directory?
- For directories, the execute bit means 'search' permission — it allows users to enter the directory and access files within it. A directory without execute permission cannot be traversed, even if read permission is set.
- Is this tool free to use?
- Yes. All Skybin developer tools are free with no account, API key, or usage limits.
- Does my data get sent to a server?
- No. Processing runs in your browser whenever possible. Sensitive input never leaves your device unless a tool explicitly fetches a URL you provide (e.g. OG Validator).
- Can I use this on mobile?
- Yes. The tools work in modern mobile browsers, though a desktop screen is easier for large JSON or PDF workflows.
- How is this different from desktop apps?
- There is nothing to install or update. Open a bookmarked URL and start working — ideal for quick tasks during development or support calls.
- Are there keyboard shortcuts?
- Most tools support standard paste (Ctrl+V / Cmd+V) and select-all in text areas. Copy buttons provide one-click output.
- Does Skybin store my history?
- No. We do not log tool inputs or outputs. Refreshing the page clears in-memory state unless the tool encodes state in the URL.