Developer API · Live

An IPA phonetic API with US, UK, and a stress-marked respelling

GET/v1/dictionary/:word

IPA transcriptions for US and UK on every word, plus an anglicized syllable breakdown that flags the stressed syllable. 100 percent coverage across 116,800+ words. No API key.

100% IPA coverageNo API keyUS + UKSyllable stress
curl https://api.quickpronounce.site/v1/dictionary/wonderful
The fields

Phonetic data on every word

Read these off the dictionary lookup. Both accents, always populated.

phonetics.us and phonetics.uk are IPA strings with primary stress marked by ˈ. syllables.us and syllables.uk are arrays of { text, stress }, where text is one syllable of the anglicized respelling and stress is 1 for the primary-stress syllable, 0 otherwise. The two accents get separate syllable arrays because the vowels and sometimes the syllable count differ.

GET /v1/dictionary/wonderful (phonetic fields)
{
  "success": true,
  "data": {
    "word": "wonderful",
    "phonetics": {
      "us": "/ˈwʌndɚfl/",
      "uk": "/ˈwʌndəfl/"
    },
    "syllables": {
      "us": [
        { "text": "wuhn", "stress": 1 },
        { "text": "derfl", "stress": 0 }
      ],
      "uk": [
        { "text": "wuhn", "stress": 1 },
        { "text": "duhfl", "stress": 0 }
      ]
    }
  }
}
Two notations

IPA vs the anglicized respelling

You get both on every word. They're for different readers.

IPA string

/ˈwʌndɚfl/
Notation
International Phonetic Alphabet symbols.
Who reads it
Learners and linguists who know the symbols. Precise but opaque to everyone else.
Best for
Dictionary displays, language courses, phonetics tooling, TTS front-ends.
Stress shown as
The ˈ mark before the stressed syllable in the string.

Anglicized respelling

WUHN-derfl
Notation
Plain English letters that approximate the sound.
Who reads it
Any English speaker, no training needed. Less precise, much more approachable.
Best for
General audiences, tooltips, name-pronunciation guides, kids' content.
Stress shown as
A stress: 1 flag on the syllable object, so you decide.

The respelling with per-syllable stress flags is the part most free phonetic APIs skip. It's what lets you show a pronunciation to someone who has never studied IPA. For a deeper explanation of the notation itself, see the IPA guide and the word stress guide.

Quick start

Read the phonetics in code

It's one field access. These match the runnable copies in the API repo's examples folder.

curl https://api.quickpronounce.site/v1/dictionary/wonderful \
  | jq '{ phonetics: .data.phonetics, syllables: .data.syllables }'
The stress flag

Working with the stress array

One stressed syllable per word. You decide how it looks.

The stress flag keeps presentation out of the data. Uppercase the stressed syllable for a shouty guide, wrap it in <strong> for a subtle one, prepend a ˈ to match IPA convention, or use it to time a highlight against the audio from the pronunciation endpoint.

Rendering the respelling
// Render the anglicized respelling with the stressed syllable marked.
const render = (syllables) =>
  syllables
    .map((s) => (s.stress === 1 ? s.text.toUpperCase() : s.text))
    .join("-");

render(data.syllables.us);   // "WUHN-derfl"

// Or wrap the stressed syllable for styling instead of shouting it:
syllables.map((s) =>
  s.stress === 1 ? <strong key={s.text}>{s.text}</strong> : s.text
);
In the wild

Where it fits

Anywhere a word needs to show how it sounds, not just what it means.

Dictionary and glossary sites

Show the IPA string for readers who want it and the respelling for readers who don't, from the same single response.

Language-learning curricula

Attach a phonetic transcription and a stress pattern to every vocabulary item without hand-transcribing thousands of words.

Text-to-speech front-ends

Display how a word should sound next to the play button, so a learner can check their reading against the audio.

Name and term pronunciation guides

Give a plain respelling with the stressed syllable marked for onboarding docs, style guides, or broadcast scripts.

Linguistics and NLP tooling

Pull US and UK transcriptions in bulk for analysis, alignment, or building a lexicon, one word per request.

Accessibility tools

Offer a phonetic hint for uncommon words in a passage so a reader can decode them without leaving the page.

FAQ

Frequently Asked Questions

Straight answers on cost, limits, licensing, and how this compares to the alternatives.

Is this real IPA?
Yes. The phonetics.us and phonetics.uk fields are International Phonetic Alphabet strings with primary stress marked by the ˈ symbol. They're broad phonemic transcriptions, the kind a dictionary prints, not narrow allophonic detail.
Do I get both US and UK transcriptions?
Every word has both. phonetics.us and phonetics.uk are always populated, and the syllable breakdown has a us and a uk array too, because the syllable count and vowels can differ between accents.
What is the anglicized syllable respelling?
It's the pronunciation written in ordinary English letters, split into syllables, with the stressed one flagged. So wonderful becomes [{text: 'wuhn', stress: 1}, {text: 'derfl', stress: 0}]. It's the piece most free phonetic APIs don't provide, and it's what you show to an audience that can't read IPA.
How do I read the stress value?
Each syllable object has stress: 1 for the primary-stress syllable and stress: 0 for the rest. There's one stressed syllable per word. You choose how to present it: uppercase it, bold it, put an accent mark before it, or drive an audio highlight from it.
Where does the phonetic data come from?
It's derived from Wiktionary (CC BY-SA 4.0) with pronunciation data drawing on CMUdict and WordNet, then normalized to a consistent notation. IPA and syllable coverage is 100 percent across the roughly 116,800 words in the dataset.
How accurate is it, and are there known gaps?
For common and mid-frequency vocabulary it's solid. Rare words, proper nouns, and recent coinages are thinner, and a handful of entries carry a single accent's transcription applied to both. If you hit a word that looks wrong, report it and it gets fixed in the dataset.
Which endpoint do I call for phonetic data?
Use GET /v1/dictionary/:word and read the phonetics and syllables fields. The same data also rides along with the pronunciation endpoint if you want the audio clip in the same response.
Do I need an API key, and what are the limits?
No key. The lookup allows 60 requests per minute and 1,000 per day per IP, enforced as a fair-use threshold during public testing. Cache results by lowercased word to stay well under it.
Can I download every transcription at once?
Not through the API. Bulk access to the full enriched dataset (IPA, syllables, definitions, everything) is a separate one-time licensed download. The API is for per-word lookups in an application.
Does it generate a pronunciation for words that aren't in the dictionary?
No. It's dictionary-backed, not a grapheme-to-phoneme model, so an invented or misspelled word returns 404 rather than a guessed transcription.
Can I use it commercially?
Yes, within fair-use limits. Keep a Wiktionary CC BY-SA 4.0 attribution line wherever you reproduce the transcriptions or the definitions. See the main API page for suggested wording.

Build on it today

The free tier is live and works for prototypes, side projects, and small production apps. Paid plans for higher request volumes are planned as usage grows. For early access or a dedicated API key now, get in touch. The full enriched dataset is also available as a one-time licensed download, separate from API access.

Dictionary content is derived in part from Wiktionary, used under CC BY-SA 4.0, with definitions and examples rewritten and enriched by QuickPronounce. Pronunciation data draws on CMUdict and WordNet.