chmod & umask

Client

Toggle rwx for owner, group, and other. Read off numeric octal, ls-style permissions, and copy a chmod prefix. umask quick reference explains typical new file and directory defaults—pair with the cron helper and pseudo-CLI when you script deployments.

Local reference: this page does not change files on disk. Use the checkboxes to match what chmod or tar unpack would show for rwxrwxrwx and numeric mode.
Owner
7
Group
6
Other
6
ls-style stringrwxrw-rw-
Numeric (octal)766

umask quick reference

New file mode: 666 & ~umask · new directory: 777 & ~umask (core bits only; special bits like setuid are not shown here).

  • umask 022 → file 644, dir 755 (typical on many distros)
  • umask 002 → file 664, dir 775 (group-writable default)

Common use cases

  • Match a `chmod` or tar listing when documentation only gives 0644, 0755, or rwxr-xr-x.
  • Compare a planned permission triple against what `umask` on your shell would leave for new files vs directories.
  • Paste a 3-digit mode in the address bar: `?q=644` or `?q=755` to start from that mode.

Common mistakes to avoid

  • Forgetting the leading digit on `chmod`

    Omitting a leading 0 in scripts can be ambiguous on some systems; we show both `644` and `0644` style copy for shells.

  • Treating this page as a remote `chmod`

    Nothing here touches your files or server—copy the command to your own terminal when you are ready to apply it.

  • Assuming umask is the same on every host

    CI images, Mac defaults, and containers can differ. Use the reference below as a pattern, not a guarantee.

FAQ

What about setuid, setgid, or sticky (fourth digit)?

This helper focuses on the common three-digit owner/group/other bits. If you need special bits, set them with your platform’s tool or docs—the numeric 4+ digit form is not shown here yet.

Is my data sent anywhere?

No. Toggles and numbers stay in the browser tab, like other Toolcore client tools.

How do I open this with a mode prefilled for agents or docs?

Use `?q=755` (or `qb=` Base64) with three octal characters 0–7—see the agent manifest for this tool id (`chmod-calculator`).

Common search terms

Phrases people search for that match this tool. See the full long-tail keyword index.

  • chmod calculator online 755 644
  • unix rwxrwxrwx to octal
  • umask 022 new file mode online
  • copy chmod command from permissions

More tools

Related utilities you can open in another tab—mostly client-side.