Art Institute of Chicago vs Metropolitan Museum of Art

The Art Institute of Chicago publishes its full collection of 130,000+ objects as a versioned, keyless REST API (api.artic.edu/api/v1) built on the same data that powers its own website and mobile app, with IIIF-based endpoints for zoomable, high-resolution images. A live GET against a real artwork record returned genuine JSON carrying Access-Control-Allow-Origin: *, reconfirming both auth None and cors yes with no key required.

The Met's Collection API exposes all 502,000+ objects in its Open Access collection — the same data behind its own site — fully keyless and free, asking only that callers self-throttle to 80 requests per second. A live GET against the real gateway, collectionapi.metmuseum.org, returned genuine object data carrying Access-Control-Allow-Origin: *, correcting cors no -> yes while reconfirming auth None.