JSON formatter & validator
Format, beautify, validate, and minify JSON online. Pinpoint syntax errors by line and column, sort keys, and copy or download the result.
Chmod calculator
Calculate Linux chmod permissions in numeric (755) and symbolic (rwxr-xr-x) form, including setuid, setgid, and sticky bits.
| Read | Write | Execute |
|---|
How to use Chmod calculator
Work out Linux file permissions for chmod. Tick read, write, and execute for owner, group, and others, or type a number like 755 or a string like rwxr-xr-x. Everything stays in sync.
- Supports setuid, setgid, and the sticky bit (4-digit modes like 2775)
- Shows numeric and symbolic chmod commands and how
ls -ldisplays them - Presets for common files, scripts, folders, and SSH keys
Chmod calculator FAQs
Is Chmod calculator free?
Chmod calculator is a free online tool on ReallyUseful.Tools. No account is required.
Does Chmod calculator run in my browser?
Chmod calculator is designed to run in your browser where supported, so files can stay on your device instead of being uploaded to a server.
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