16 Dictionaries APIs

Dictionaries APIs let you add dictionaries capabilities without building from scratch. Every entry below is profiled with trust signals — pricing model, authentication requirements, CORS support, rate limits, and live uptime checks — so you can compare options and pick production-safe choices instead of guessing from a link list.

definitionstranslationssynonymspronunciationspellinglanguage
APIPricingAuthCORSHealth
ApyHub Translate
Translate text between 50+ languages using ApyHub's translation utility API.
FreeNoYesProfile
Chinese Character Web
Chinese character definitions and pronunciations
FreeNoNoProfile
Chinese Text Project
Online open-access digital library for pre-modern Chinese texts
FreeNoUnknownProfile
Collins
Bilingual Dictionary and Thesaurus Data
FreeAPI KeyNoProfile
Free Dictionary
Definitions, phonetics, pronounciations, parts of speech, examples, synonyms
FreeNoNoProfile
HelloSalut
Get hello translation following user language
FreeNoNoProfile
Indonesia Dictionary API
Indonesia dictionary many words
UnknownUnknownUnknownProfile
Lingua Robot
Word definitions, pronunciations, synonyms, antonyms and others
FreeAPI KeyNoProfile
Merriam-Webster
Dictionary and Thesaurus Data
FreeAPI KeyNoProfile
OwlBot API
Definitions with example sentence and photo if available
UnknownAPI KeyYesProfile
Oxford
Dictionary Data
FreeAPI KeyNoProfile
Synonyms
Synonyms, thesaurus and antonyms information for any given word
FreeAPI KeyNoProfile
Wiktionary
Collaborative dictionary data
FreeNoNoProfile
Wiktionary API
Wiktionary API: free dictionary data, word definitions, etymologies, and translations in 100+ languages.
FreeUnknownYesProfile
Wordnik
Dictionary Data
FreeAPI KeyNoProfile
Words
Definitions and synonyms for more than 150,000 words
FreeAPI KeyNoProfile

How to choose a dictionaries API

Start with pricing and auth: free tiers and no-auth APIs are fastest to prototype with. Then check CORS if your app calls the API from the browser, and health before you commit — a great API that's been down for a week will block your launch. Each profile below shows all of these signals plus rate limits where documented.