free-translation-api

# Free Translation API — LibreTranslate

Translate text between 100+ languages using free LibreTranslate instances. Open-source, privacy-respecting alternative to Google Translate API ($20/million characters).

## Why This Replaces Paid Translation APIs

**💰 Cost savings:**
- ✅ **100% free** — no API keys required for public instances
- ✅ **No rate limits** — generous limits on public instances
- ✅ **Open source** — self-hostable for unlimited usage
- ✅ **Privacy-first** — no data collection or tracking

**Perfect for AI agents that need:**
- Text translation without Google Translate API costs
- Privacy-respecting translation (no data retention)
- High volume translation without quotas
- Offline translation capability (self-hosted)

## Quick comparison

| Service | Cost | Rate limit | Privacy | API key required |
|---------|------|------------|---------|------------------|
| Google Translate API | $20/1M chars | Unlimited with payment | ❌ Tracked | ✅ Yes |
| DeepL API | $5-25/1M chars | 500k chars/month free | ❌ Tracked | ✅ Yes |
| **LibreTranslate** | **Free** | **Varies by instance** | **✅ Private** | **❌ No** |

## Skills

### translate_text

Basic text translation using LibreTranslate.

```bash
# Translate text (English to Spanish)
curl -s -X POST "https://libretranslate.com/translate" \
  -H "Content-Type: application/json" \
  -d '{
    "q": "Hello, how are you?",
    "source": "en",
    "target": "es"
  }' | jq -r '.translatedText'

# Auto-detect source language
curl -s -X POST "https://libretranslate.com/translate" \
  -H "Content-Type: application/json" \
  -d '{
    "q": "Bonjour le monde",
    "source": "auto",
    "target": "en"
  }' | jq -r '.translatedText'

# Translate from file
TEXT=$(cat document.txt)
curl -s -X POST "https://libretranslate.com/translate" \
  -H "Content-Type: application/json" \
  -d "{
    \"q\": \"$TEXT\",
    \"source\": \"en\",
    \"target\": \"fr\"
  }" | jq -r '.translatedText' > document_fr.txt
```

**Node.js:**

```javascript
async function translateText(text, targetLang, sourceLang = 'auto', instance = 'https://libretranslate.com') {
  const res = await fetch(`${instance}/translate`, {
    method: 'POST',
    headers: { 'Content-Type': 'application/json' },
    body: JSON.stringify({
      q: text,
      source: sourceLang,
      target: targetLang
    })
  });
  
  if (!res.ok) {
    const error = await res.text();
    throw new Error(`Translation failed: ${error}`);
  }
  
  const data = await res.json();
  return data.translatedText;
}

// Usage
// translateText('Hello world', 'es', 'en')
//   .then(translated => console.log(translated));
// Output: "Hola mundo"
```

### get_supported_languages

List all supported languages for an instance.

```bash
# Get all supported languages
curl -s "https://libretranslate.com/languages" | jq '.[] | {code: .code, name: .name}'

# Get language codes only
curl -s "https://libretranslate.com/languages" | jq -r '.[].code'

# Check if specific language is supported
curl -s "https://libretranslate.com/languages" | jq -r '.[] | select(.code == "ja") | .name'
```

**Node.js:**

```javascript
async function getSupportedLanguages(instance = 'https://libretranslate.com') {
  const res = await fetch(`${instance}/languages`);
  const languages = await res.json();
  return languages.map(lang => ({
    code: lang.code,
    name: lang.name
  }));
}

// Usage
// getSupportedLanguages().then(langs => {
//   console.log('Supported languages:', langs.length);
//   langs.slice(0, 10).forEach(l => console.log(`${l.code}: ${l.name}`));
// });
```

### detect_language

Detect the language of a text.

```bash
# Detect language
curl -s -X POST "https://libretranslate.com/detect" \
  -H "Content-Type: application/json" \
  -d '{
    "q": "Bonjour, comment allez-vous?"
  }' | jq -r '.[0] | {language: .language, confidence: .confidence}'

# Detect language for multiple texts
curl -s -X POST "https://libretranslate.com/detect" \
  -H "Content-Type: application/json" \
  -d '{
    "q": "Hola mundo. Cómo estás?"
  }' | jq -r '.[]'
```

**Node.js:**

```javascript
async function detectLanguage(text, instance = 'https://libretranslate.com') {
  const res = await fetch(`${instance}/detect`, {
    method: 'POST',
    headers: { 'Content-Type': 'application/json' },
    body: JSON.stringify({ q: text })
  });
  
  if (!res.ok) {
    throw new Error('Language detection failed');
  }
  
  const results = await res.json();
  return results[0]; // Returns {language: 'en', confidence: 0.99}
}

// Usage
// detectLanguage('Hello world')
//   .then(result => console.log(`Detected: ${result.language} (${result.confidence})`));
```

### batch_translate

Translate multiple texts or paragraphs.

```bash
#!/bin/bash
# Translate multiple lines from a file
INPUT_FILE="content_en.txt"
OUTPUT_FILE="content_es.txt"
TARGET_LANG="es"

> "$OUTPUT_FILE"  # Clear output file

while IFS= read -r line; do
  if [ -n "$line" ]; then
    translated=$(curl -s -X POST "https://libretranslate.com/translate" \
      -H "Content-Type: application/json" \
      -d "{
        \"q\": \"$line\",
        \"source\": \"auto\",
        \"target\": \"$TARGET_LANG\"
      }" | jq -r '.translatedText')
    
    echo "$translated" >> "$OUTPUT_FILE"
    sleep 1  # Rate limiting
  fi
done < "$INPUT_FILE"

echo "Translation complete: $OUTPUT_FILE"
```

**Node.js:**

```javascript
async function batchTranslate(texts, targetLang, sourceLang = 'auto', delayMs = 1000) {
  const results = [];
  
  for (const text of texts) {
    try {
      const translated = await translateText(text, targetLang, sourceLang);
      results.push({ original: text, translated, success: true });
      
      // Rate limiting delay
      if (delayMs > 0) {
        await new Promise(resolve => setTimeout(resolve, delayMs));
      }
    } catch (err) {
      results.push({ original: text, translated: null, success: false, error: err.message });
    }
  }
  
  return results;
}

// Usage
// const texts = [
//   '