chmod API
A Unix file-permission calculator as an API. Convert a symbolic permission string (rwxr-xr-x) to its octal mode (755) and back, and explain any mode in plain English with a per-class breakdown (owner / group / others, each read / write / execute). Full support for the special bits — setuid (4), setgid (2) and the sticky bit (1) — so 4755 ↔ rwsr-xr-x and 1777 ↔ rwxrwxrwt are handled correctly, including the capital S/T forms. Perfect for Dockerfiles and CI scripts, deployment and provisioning tooling, teaching, and any time you need to double-check a chmod value. Pure local computation — no key, no third-party service, instant. Live, nothing stored. 4 endpoints. Distinct from anything that touches real files or networking.
api.oanor.com/chmod-api