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Free Dictionary API

Free dictionary API with no key: definitions, phonetics, audio pronunciation, synonyms, antonyms and examples for English words. Tested curl example.

No API key requiredCORS enabledHTTPSFree tier

Endpoint tested and returned HTTP 200 on 2026-08-19

What is the Free Dictionary API?

The Free Dictionary API is a key-free API returning English word definitions, phonetic transcriptions, audio pronunciation URLs, parts of speech, synonyms, antonyms and usage examples.

This API is remarkably complete for something entirely free and unauthenticated. A single lookup returns every sense of a word grouped by part of speech, plus IPA phonetics and — most usefully — hosted audio pronunciation files you can play directly.

The structure is deeply nested, which is the main integration challenge: the response is an array of entries, each with an array of meanings, each with an array of definitions. Expect three levels of iteration to render everything a word offers.

Quick facts

Base URL
https://api.dictionaryapi.dev/api/v2/entries/en
Authentication
No key required.
Rate limit
No published limit; fair use expected.
Pricing
Free and open source.
CORS
Enabled — callable directly from browser JavaScript
Official docs
Read the docs

How to use the Free Dictionary API

Every request below was executed against the live API on 2026-08-19, and the response shown is the real body it returned — not an illustration.

1. Look up the definition of a word

GET https://api.dictionaryapi.dev/api/v2/entries/en/hello

curl
curl 'https://api.dictionaryapi.dev/api/v2/entries/en/hello'
JavaScript (fetch)
const res = await fetch("https://api.dictionaryapi.dev/api/v2/entries/en/hello");
if (!res.ok) throw new Error(`Request failed: ${res.status}`);
const data = await res.json();
console.log(data);
Python (requests)
import requests

res = requests.get("https://api.dictionaryapi.dev/api/v2/entries/en/hello", timeout=20)
res.raise_for_status()
print(res.json())
Response — HTTP 200 (truncated)
[
  {
    "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.wikimedia.org/w/index.php?curid=9021983",
        "license": {
          "name": "BY 3.0 US",
          "url": "https://creativecommons.org/licenses/by/3.0/us"
        }
      },
      {
        "text": "/həˈloʊ/",
        "audio": ""
      }
    ],
    "meanings": [
      {
        "partOfSpeech": "noun",
        "definitions": [
          {
            "definition": "\"Hello!\" or an equivalent greeting.",
            "synonyms": [],
            "antonyms": []
          }
        ],
        "synonyms": [
          "greeting"
        ],
        "antonyms": []
      },
      {
        "partOfSpeech": "verb",
        "definitions": [
          {
            "definition": "To greet with \"hello\".",
            "synonyms": [],
            "antonyms": []
          }
        ],
        "synonyms": [],
        "antonyms": []
      },
      {
        "partOfSpeech": "interjection",
        "definitions": [
          {
            "definition": "A greeting (salutation) said when meeting someone or acknowledging someone’s arrival or presence.",
            "synonyms": [],

Parameters

ParameterTypeRequiredDescription
<word>pathRequiredThe word to define. hello
<lang>pathOptionalLanguage code in the path; `en` is best supported. en

Response fields

[].wordstring
The word looked up.
[].phoneticstring
IPA phonetic transcription.
[].phonetics[].audiostring
URL to an audio pronunciation file, often empty for some entries.
[].meanings[].partOfSpeechstring
noun, verb, adjective and so on.
[].meanings[].definitions[].definitionstring
The definition text.
[].meanings[].definitions[].examplestring
Usage example, when available.
[].meanings[].synonyms / antonymsarray
Related words at meaning level.

What you can build with the Free Dictionary API

  • Build a dictionary or vocabulary learning app with audio pronunciation
  • Add definition tooltips to technical documentation
  • Create word games that need to validate real words
  • Support language learners with phonetics and usage examples

Common errors and how to fix them

404 with a title/message object

Word not found — the shape differs from a successful lookup.

Fix: Check for the `title` field before assuming you received an array.

Empty audio field

Not every phonetic entry has a recording.

Fix: Iterate the `phonetics` array and use the first entry with a non-empty audio URL.

Free Dictionary API — frequently asked questions

Is there a free dictionary API with no API key?

Yes. The Free Dictionary API returns definitions, phonetics, audio pronunciation, synonyms and examples for English words with no key or signup.

Does it provide audio pronunciation?

Yes, in the `phonetics` array as hosted audio file URLs. Not every entry has one, so iterate and pick the first with a non-empty `audio` value.

Why is the response structure so nested?

A word can have several entries, each with several parts of speech, each with several definitions. Rendering everything requires iterating three levels: entries, meanings, then definitions.

What happens when a word is not found?

You get HTTP 404 with an object containing `title`, `message` and `resolution` — a completely different shape from the success response, so check for it before treating the result as an array.

Tools that pair with this API

Free Dictionary API is an independent third-party service and is not affiliated with ByteTools or ByteVancer. Details on this page were verified on 2026-08-19; always check the official documentation before relying on this API in production, as terms and limits can change.