Category: Knowledge · Auth: none · Status on 2026-10-05: OK (HTTP 200) · 64 ms
Dictionary API is a free knowledge API that needs no key. On 2026-10-05 00:08 UTC our sweep found it live, answering HTTP 200 in 64 ms.
Definitions, phonetics, synonyms, examples for English words. Zero setup.
These auth and limit details come from our curated field guide, as the provider documented them when the entry was written or last corrected. The daily sweep checks that the API answers; it does not re-verify the provider's limits, so check the documentation before relying on a number.
Field-guide note: SLOW as of 2026-09-08 — reads DOWN in our sweep, and the reason is latency, not an outage. The endpoint still answers 200 with correct data, but takes ~19.4s consistently, against our 10s probe timeout; one attempt in four did not complete inside 30s. First observed DOWN in the 2026-08-28 build and unbroken since, so this is a settled degradation rather than a blip. Usable if you can wait ~20s per word and set your client timeout accordingly; not usable in an interactive or agent loop that assumes a fast lookup.
This is the exact probe the sentinel runs each sweep — one read-only GET. The result above carries the date it was measured:
curl -s 'https://api.dictionaryapi.dev/api/v2/entries/en/hello'Captured 2026-10-05 00:08 UTC (application/json, first 400 chars):
[{"word":"hello","phonetics":[{"audio":"https://api.dictionaryapi.dev/media/pronunciations/en/hello-au.mp3","sourceUrl":"https://commons.wikimedia.org/w/index.php?curid=75797336","license":{"name":"BY-SA 4.0","url":"https://creativecommons.org/licenses/by-sa/4.0"}},{"text":"/həˈləʊ/","audio":"https://api.dictionaryapi.dev/media/pronunciations/en/hello-uk.mp3","sourceUrl":"https://commons.wikimediaOnce per sweep the sentinel sends one read-only GET to the URL above, with a descriptive user-agent and a 10-second timeout, and records the HTTP status, the round-trip time, the content type and the first few hundred characters of the response. Only a timeout is re-probed, once, with a 45-second ceiling. The status measured on 2026-10-05, OK, means the probe got a 2xx or 3xx response within the 10-second timeout. One reading is one sweep from one shared network address, not a guarantee of uptime: a per-IP rate limit can read as an error on our side.
The same measurement is in the api-health.json feed, dated by its generated_at; filter results on name == "Dictionary API". An MCP client can call the check_api_health tool at /mcp with {"api": "Dictionary API"}; it answers from the same feed.
Checked 2026-10-05 00:08 UTC by the AI Deals Sentinel. Machine-readable: api-health.json.