Skip to main content
Identify the language of text with confidence scores. Useful for routing multilingual content or determining if translation is needed.
Endpoint
POST /translate/v1/detect

import Casedev from 'casedev';

const client = new Casedev({ apiKey: 'sk_case_YOUR_API_KEY' });

const result = await client.translate.v1.detect({
  q: 'Bonjour, comment allez-vous?'
});

const detection = result.data.detections[0][0];
console.log(detection.language);   // "fr"
console.log(detection.confidence); // 0.98
Response
{
  "data": {
    "detections": [
      [
        {
          "language": "fr",
          "confidence": 0.98,
          "isReliable": true
        }
      ]
    ]
  }
}

​
Parameters

ParameterTypeRequiredDescription
qstring or string[]YesText to detect language for. Can be a single string or array for batch detection.

​
Response

The response contains an array of detections. Each detection includes:
FieldTypeDescription
languagestringDetected language code (ISO 639-1)
confidencenumberConfidence score from 0 to 1
isReliablebooleanWhether the detection is considered reliable

​
Batch detection

Detect languages for multiple texts in a single request: 
const result = await client.translate.v1.detect({
  q: [
    'Hello, how are you?',
    'Hola, como estas?',
    'Bonjour, comment ca va?',
    'Guten Tag, wie geht es Ihnen?'
  ]
});

result.data.detections.forEach((detection, i) => {
  console.log(`Text ${i + 1}: ${detection[0].language}`);
});
// Text 1: en
// Text 2: es
// Text 3: fr
// Text 4: de

​
Examples

​
Route content by language

async function routeByLanguage(text: string) {
  const result = await client.translate.v1.detect({ q: text });
  const lang = result.data.detections[0][0].language;

  switch (lang) {
    case 'en':
      return processEnglish(text);
    case 'es':
      return processSpanish(text);
    default:
      // Translate to English first
      const translated = await client.translate.v1.translate({
        q: text,
        target: 'en',
        source: lang
      });
      return processEnglish(translated.data.translations[0].translatedText);
  }
}

​
Filter by language confidence

const result = await client.translate.v1.detect({
  q: foreignText
});

const detection = result.data.detections[0][0];

if (detection.confidence > 0.9 && detection.isReliable) {
  console.log(`Confident detection: ${detection.language}`);
} else {
  console.log('Low confidence, may need manual review');
}

​
Identify mixed-language documents

// Split document into paragraphs and detect each
const paragraphs = document.split('\n\n');

const result = await client.translate.v1.detect({
  q: paragraphs
});

const languages = new Set(
  result.data.detections.map(d => d[0].language)
);

if (languages.size > 1) {
  console.log('Mixed-language document detected');
  console.log('Languages found:', [...languages].join(', '));
}
Pricing: $0.05 per 1,000 characters, same as translation.