Free Dictionary API
Free dictionary API with no key: definitions, phonetics, audio pronunciation, synonyms, antonyms and examples for English words. Tested curl example.
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 'https://api.dictionaryapi.dev/api/v2/entries/en/hello'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);import requests
res = requests.get("https://api.dictionaryapi.dev/api/v2/entries/en/hello", timeout=20)
res.raise_for_status()
print(res.json())[
{
"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
| Parameter | Type | Required | Description |
|---|---|---|---|
<word> | path | Required | The word to define. hello |
<lang> | path | Optional | Language 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
Word Counter
Count words, characters, sentences, paragraphs and estimated reading time instantly. Free online word counter for essays, blogs and social media.
Character Counter
Count characters with and without spaces in real time and check limits for Twitter/X, Instagram captions, meta descriptions and SMS messages.
JSON Formatter
Format, beautify and minify JSON online with 2-space, 4-space or tab indentation. Sort keys alphabetically and catch syntax errors instantly — free and private.
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.