This site sports a very simple API for retrieving the synonyms for any word. You access the API by making a GET request:

http://words.bighugelabs.com/api/{version}/{api key}/{word}/{format}

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api key
Your API key.
The word you want to lookup.
format (optional)
json, php, xml. If left off then the response defaults to newline delimited plain text.
JSON callback function (optional)
See examples below


The response is always an array. 'xml' and 'json' should be self-explanatory. The 'php' format is a serialized PHP array that can be unserialized with the unserialize() function. The plain text response is pipe and newline delimited.


Relationship types are "syn" for synonyms, "ant" for antonyms, "rel" for related terms, "sim" for similar terms, and "usr" for user suggestions. Not all parts of speech or relationship types are guaranteed to be available for all words so test for their existence before using them.

Version 1 of the API is deprecated. If you are using it, you should upgrade as soon as possible.

You can also view a sample administration page that comes with every API key: Sample admin page

Security and CORS

This server sends the Access-Control-Allow-Origin: * CORS header for all API requests. This allows you to use a JavaScript client in a web browser to make requests to the API. Please note that this is insecure and will allow anyone to see your API key. We strongly recommended that you use a server-side proxy to keep your key secret in all public clients.

HTTP Response Codes

200 OK: The word was found and the results are in the body

303 {alternate}: The original word was not found but an alternative has been. The alternative is the HTTP response message. For example, a request for "reminding" returns 303 remind. The Location header contains the URL for the API request for "remind."

404 Not Found: No data could be found for the word or alternates

500 Usage Exceeded: Usage limits have been exceeded

500 Inactive key: The key is not active

500 Missing words: No word was submitted

500 Not whitelisted: The IP address was blocked

Please ensure that your application does not continue to make requests after you receive a "Usage exceeded" error until the following day (in GMT-8).

Third party API kits

These are wrappers for the Thesaurus API written by third parties. Send me a link to your publicly hosted API kit if you'd like to include it on this page.

Uptime status

Click to view the 7-day uptime status report


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Terms of use

* If you're doing anything related to SEO (article spinning, for example), odds are you are doing something slimy. It won't work anyway.

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