M
API Matrix

Collins API

Dictionaries / API Key Intermediate HTTPS
Varies by plan (check documentation)
42 Score
Grade D
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Overview

Collins Dictionary API gives developers access to comprehensive bilingual dictionary and thesaurus data for multiple language pairs, including English, Spanish, French, and more. It returns definitions, translations, example sentences, and audio pronunciations from the authoritative Collins lexical database. An API key is required and must be requested directly from Collins.

💡

Beginner Tip

Use the /search endpoint first to find the exact entry ID for a word, then pass that ID to /entries for full definition data. This two-step approach avoids 404 errors from spelling variations.

Available Data

word definitions
pronunciation
synonyms and antonyms
example sentences
part of speech

Example Response

JSON Response 
{
  "word": "serendipity",
  "phonetic": "/ˌsɛr.ənˈdɪp.ɪ.ti/",
  "meanings": [
    {
      "partOfSpeech": "noun",
      "definition": "The occurrence of events by chance in a happy way"
    }
  ],
  "synonyms": [
    "luck",
    "fortune",
    "chance"
  ]
}

Field Reference

entryId Unique identifier for the dictionary entry.
headword The word or phrase as it appears as the main entry in the dictionary.
definitions List of definition objects, each containing the sense and example sentences.
translations List of translation objects for bilingual dictionary queries.
audioFile URL to an MP3 pronunciation file for the headword.

Implementation Example 

const url = "https://api.collinsdictionary.com/api/v1/documentation/html/";
// Replace headers or query params with the values required by this API.
const response = await fetch(url, {
  headers: {
  "X-API-Key": "YOUR_API_KEY"
  }
});
if (!response.ok) throw new Error(`Request failed: ${response.status}`);
const data = await response.json();
console.log(data);

What Can You Build?

Note: These code examples are AI-generated and unverified. Always refer to the official API documentation for accurate usage.

Common Errors & Troubleshooting

403 Forbidden The accessKey header is missing or the key has not been activated.
✓ Ensure you pass the key in the accessKey request header (not as a query param) and that your account is approved.
404 Not Found on /entries The entry ID provided does not exist in the selected dictionary.
✓ Use the /search endpoint first to retrieve the correct entryId, then query /entries/{entryId}.
Language pair not available The dictionary code used does not correspond to an active bilingual dictionary.
✓ Call GET /dictionaries to list all available dictionary codes for your subscription tier.

Matrix Score Breakdown

🌐 Reachability 0/30
⚡ Speed 15/20
🔒 Security 15/15
🛠 Developer XP 12/20
✓ Reliability 0/15

Partially tested on Apr 5, 2026

Technical Specifications

Auth API Key
HTTPS REQUIRED
CORS UNKNOWN
Category Dictionaries
Difficulty Intermediate
Verified: 2026-04-04

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