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Install guideInteractive Unix file permission calculator. Toggle permissions or enter octal directly.
| Read | Write | Execute | Octal | |
|---|---|---|---|---|
| Owner | 7 | |||
| Group | 5 | |||
| Others | 5 |
Calculate Unix file permission modes and symbolic flags to reduce mistakes in deployment scripts, CI jobs, and system administration tasks.
It maps read, write, and execute flags to numeric and symbolic chmod values.
It helps verify permission settings before applying changes to files and directories.
It supports faster debugging of access errors caused by incorrect permission combinations.
Numeric mode
755
Symbolic mode
u+rwx,g+rx,o+rx
Directory policy
owner full access, group read, others none
Mode translation
755 => rwxr-xr-x
Symbolic conversion
rwxr----- => 740
Ops note
Apply least privilege and verify ownership with chown when needed.
Accidentally granting world-writable access
Review others permissions before applying changes.
Script fails due to missing execute bit
Set execute permission for required user or group.
Directory traversal blocked unexpectedly
Ensure execute bit is set on directories that need traversal.
Permission appears correct but access still denied
Check file ownership, ACLs, and parent directory permissions.
Chmod Calculator should be treated as a repeatable validation step before merge, release, and handoff.
What does chmod 755 mean?
Owner can read/write/execute, group and others can read/execute.
Should files always be executable in scripts repos?
Only scripts and binaries that need execution should have execute bits.
Is 777 ever appropriate?
Rarely; it is usually too permissive for production systems.
Why does permission change not solve access issue?
Ownership, ACLs, SELinux, or parent directory rules may still block access.