Calculate resulting file (666) and directory (777) permissions from umask values.
Execution runs 100% locally inside the browser sandbox using HTML5 Canvas, Web Cryptography Subtle API, and Web Workers. Zero egress.
Zero network latency. Operates completely offline with zero dependencies on third-party backend servers or cloud services.
Built according to official RFC specifications, cryptographic test vectors, and enterprise-grade data transformation standards.
Type an octal umask value like 022 or 027.
Review the resulting file permissions (base 666).
Review the resulting folder permissions (base 777).
By default, POSIX does not grant execution (+x) permission to newly created regular files for security reasons.
027 gives full access to owner, read/execute to group, and completely blocks other users (files: 640, dirs: 750).
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