Translation API Comparison 2026

DeepL API (Node.js)

// npm install deepl-node
const deepl = require('deepl-node');

const translator = new deepl.Translator('YOUR_AUTH_KEY');

async function translateText() {
  const result = await translator.translateText(
    'Hello, how are you?',
    null,     // auto-detect source language
    'es',     // target language
    { formality: 'prefer_more' }  // formal tone
  );
  console.log(result.text);
  // Output: "Hola, ¿cómo está usted?"
}

translateText();

DeepL API (Python)

# pip install deepl
import deepl

translator = deepl.Translator("YOUR_AUTH_KEY")

result = translator.translate_text(
    "Hello, how are you?",
    target_lang="ES",
    formality="prefer_more"
)

print(result.text)
# Output: "Hola, ¿cómo está usted?"
print(result.detected_source_lang)
# Output: "EN"

Azure Translator (cURL)

# Simple REST API call - works with any language
curl -X POST "https://api.cognitive.microsofttranslator.com/translate?api-version=3.0&to=es&to=fr" \
  -H "Ocp-Apim-Subscription-Key: YOUR_KEY" \
  -H "Ocp-Apim-Subscription-Region: eastus" \
  -H "Content-Type: application/json" \
  -d '[{"Text": "Hello, how are you?"}]'

# Response: translate to MULTIPLE languages in one call
# [{"translations": [
#   {"text": "Hola, ¿cómo estás?", "to": "es"},
#   {"text": "Bonjour, comment allez-vous?", "to": "fr"}
# ]}]

Azure Translator (Node.js)

const response = await fetch(
  'https://api.cognitive.microsofttranslator.com/translate?api-version=3.0&to=es',
  {
    method: 'POST',
    headers: {
      'Ocp-Apim-Subscription-Key': 'YOUR_KEY',
      'Ocp-Apim-Subscription-Region': 'eastus',
      'Content-Type': 'application/json'
    },
    body: JSON.stringify([{ Text: 'Hello, how are you?' }])
  }
);

const data = await response.json();
console.log(data[0].translations[0].text);
// Output: "Hola, ¿cómo estás?"

LibreTranslate (Self-Hosted)

# Start LibreTranslate with Docker
docker run -ti --rm -p 5000:5000 libretranslate/libretranslate

# Translate via REST API (no API key needed)
curl -X POST "http://localhost:5000/translate" \
  -H "Content-Type: application/json" \
  -d '{"q": "Hello, how are you?", "source": "en", "target": "es"}'

# Response:
# {"translatedText": "Hola, ¿cómo estás?"}

LibreTranslate (Python)

import requests

response = requests.post(
    "http://localhost:5000/translate",
    json={
        "q": "Hello, how are you?",
        "source": "en",
        "target": "es"
    }
)

print(response.json()["translatedText"])
# Output: "Hola, ¿cómo estás?"

MyMemory - No API Key Required

# Zero setup - just a GET request!
curl "https://api.mymemory.translated.net/get?q=Hello,+how+are+you?&langpair=en|es"

# Response:
# {"responseData": {"translatedText": "Hola, ¿cómo estás?"}}

MyMemory (JavaScript - Browser Compatible)

// Works directly in the browser - no API key, no CORS issues
async function translate(text, from, to) {
  const url = `https://api.mymemory.translated.net/get?q=${encodeURIComponent(text)}&langpair=${from}|${to}`;
  const res = await fetch(url);
  const data = await res.json();
  return data.responseData.translatedText;
}

// Usage
const result = await translate('Good morning!', 'en', 'ja');
console.log(result);
// Output: "おはようございます！"

MyMemory (Python)

import requests

def translate(text, source, target):
    response = requests.get(
        "https://api.mymemory.translated.net/get",
        params={"q": text, "langpair": f"{source}|{target}"}
    )
    return response.json()["responseData"]["translatedText"]

print(translate("Good morning!", "en", "de"))
# Output: "Guten Morgen!"