Collins vs Synonyms

Collins' REST API serves the publisher's monolingual English and bilingual dictionary, thesaurus, translation and audio-pronunciation data used on collinsdictionary.com, with separate JSON and XML response representations for each resource. A live unauthenticated request against the real gateway returned a genuine application-level "NoAccessKey" 403 rather than a Cloudflare challenge, confirming the API Key requirement and that the service itself is fully live. Its own pricing page grants up to 5,000 calls/month free before metered tiers (from £50/month) kick in at higher volumes.

The Synonyms API is STANDS4 Network's word-lookup service, returning synonym, antonym, and part-of-speech data for a submitted word as either JSON or XML from a single GET request against stands4.com's shared services endpoint — the same backend that powers sibling STANDS4 properties like Rhymes.com and Definitions.net. A live GET and OPTIONS preflight against that endpoint both echoed `access-control-allow-origin: *`; the service is free for up to 100 queries/day, with a paid commercial license available by contacting STANDS4 directly.