Text Analysis APIs
Free text analysis APIs: sentiment analysis, language detection, translation, summarisation, named entity recognition, profanity filtering and readability scoring.
9 tested APIs with full docs · 9 need no key · 29 more listed
Tested, with full documentation
We called each of these before publishing. Every page carries a working curl command, the real JSON response it returned, parameters and common errors.
EmojiHub
Free emoji API with no key: random or filtered emoji with names, categories, groups, HTML entity codes and Unicode code points. Tested curl example.
Jisho
Free Japanese dictionary API with no key: search in English, kanji, kana or romaji and get readings, glosses, parts of speech and JLPT tags. Tested example included.
KanjiAPI
Free kanji API with no key: readings, meanings, stroke count, JLPT level, school grade and Heisig keyword for any character. Tested example included.
LanguageTool
Free grammar and spell checking API with no key: detect spelling, grammar and style errors in 25+ languages with suggested corrections. Tested GET and POST.
LibreTranslate
Free open-source translation API: self-hostable machine translation across 30+ languages with no data sent to commercial providers. Tested curl example.
MyMemory Translation
Free translation API with no key: machine translation plus a human translation memory across 100+ language pairs. 5,000 words/day anonymously. Tested.
PurgoMalum
Free profanity filter API with no key: remove or mask offensive words from text, with custom word lists and configurable replacement characters. Tested.
RhymeBrain
Free rhyming dictionary API with no key: rhymes scored and ranked, with syllable counts and frequency, plus portmanteau and word-info functions. Tested example included.
text-processing.com Sentiment
Free sentiment analysis API with no key: POST a block of text, get back a positive, negative or neutral label with probabilities for each class. Tested example included.
Choosing between these Text Analysis APIs
Text analysis APIs handle the natural-language jobs that are awkward to implement yourself: detecting language, scoring sentiment, extracting entities and translating between languages.
There is real overlap with the AI category, and the distinction is blurring. The APIs here tend to be narrower, cheaper and more predictable than general-purpose language models — often a better fit when you need one specific classification rather than open-ended generation.
More Text Analysis APIs in the directory
29 further APIs in this category, of which 0 need no API key. These are catalogued from the public-API lists and link straight to each provider's own documentation — we have not tested them yet, so treat the auth and CORS flags as the upstream list's claim rather than ours. They are promoted to a full tested page as we work through them.
| API | What it does | Auth |
|---|---|---|
| AI Text Moderation, Toxicity & Sentiment Analyzer | Detect sentiment, toxicity, and emotional aspects in text with AI moderation | KeyCORS |
| AI Translate text API | The Text Translation API translates text into any of the 80 supported languages, providing accurate and context-aware translations | KeyCORS |
| Analyse Keywords API | This API lets you extract high-frequency keywords, key phrases and latent semantic keywords from any URL | KeyCORS |
| apilayer languagelayer | Language Detection JSON API supporting 173 languages | OAuth |
| Audexum | Text-to-speech REST API with 43 voices and 33 languages | KeyCORS |
| Aylien Text Analysis | A collection of information retrieval and natural language APIs | Key |
| Brainiall Text-to-Speech | Pay-as-you-go multilingual text-to-speech with Portuguese voices and WAV, MP3, and Opus output | KeyCORS |
| Cloudmersive Natural Language Processing | Natural language processing and text analysis | KeyCORS |
| Code Detection | Detect, label, format and enrich the code in your app or in your data pipeline | OAuth |
| Code Detection API | Detect, label, format and enrich the code in your app or in your data pipeline | OAuth |
| Convert Text to Speech API | This API converts any text to speech automatically | KeyCORS |
| Detect Language | Detects text language | Key |
| Detect Language API | This API detects the language from any text (+ 50 languages supported) | KeyCORS |
| ELI | Natural Language Processing Tools for Thai Language | Key |
| Fuzzy Text Search API | The Fuzzy Text Search API finds close matches for user queries, handling typos and partial inputs to deliver relevant results quickly and accurately | KeyCORS |
| GeoScore | Score content for AI search citation readiness with a 0-100 GEO score and 8 structural metrics | KeyCORS |
| Google Cloud Natural | Natural language understanding technology, including sentiment, entity and syntax analysis | Key |
| Hirak OCR | Image to text -text recognition- from image more than 100 language, accurate, unlimited requests | Key |
| Hirak Translation | Translate between 21 of most used languages, accurate, unlimited requests | Key |
| Kiprio Translate | Free text translation with language detection, supports 50+ languages | KeyCORS |
| Langbly | Context-aware text translation and language detection for 100+ languages | KeyCORS |
| Lecto Translation | Translation API with free tier and reasonable prices | KeyCORS |
| Proofread and Grammar Check API | The Proofreading and Grammar Check API ensures the provided text is grammatically correct and polished by automatically proofreading and checking for errors | KeyCORS |
| Safe text | Clean short and long texts. It is probably world most complete text-cleaner API! Providing very fast and accurate results. | KeyCORS |
| Semantria | Text Analytics with sentiment analysis, categorization & named entity extraction | OAuth |
| Sentiment Analysis | Multilingual sentiment analysis of texts from different sources | KeyCORS |
| SpryTools AI Text Analysis | Sentiment, summarization, NER, zero-shot classification and keyword extraction via Gemini | Key |
| Tisane | Text Analytics with focus on detection of abusive content and law enforcement applications | OAuthCORS |
| Watson Natural Language Understanding | Natural language processing for advanced text analysis | OAuth |