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Lemonfox.ai

Lemonfox.ai

Docs
Easy-to-use AI API

Subtitle API

Generate ready-to-use SRT and VTT subtitle files from audio or video in one API call — no post-processing required.

Save 50% on Captions

$0.17 / hour

Lemonfox.ai

SRT & VTT included

$0.36 / hour

OpenAI Whisper API

JSON only by default

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SRT & VTT Output

Set response_format to srt or vtt and get a correctly timestamped subtitle file. Drop it into YouTube, Vimeo, Premiere Pro, or any HTML5 video player.

Audio & Video, 100+ Languages

Upload audio or video (mp3, mp4, mov, webm, and more) in over 100 languages. Use translate=true to produce English captions from non-English speech.

Lowest Price

Subtitle generation uses the same rate as transcription — $0.50 per 3 hours of audio ($0.17/hour). No separate captioning fee.

Simple API Setup

Request subtitles by setting response_format to srt (SubRip) or vtt (WebVTT). The API returns a ready-to-use subtitle file — no custom formatter needed.

const body = new FormData();
body.append('file', 'https://output.lemonfox.ai/wikipedia_ai.mp3');
// Audio or video files work — mp3, wav, mp4, mov, webm, and more
body.append('response_format', 'srt');
body.append('language', 'english');

fetch('https://api.lemonfox.ai/v1/audio/transcriptions', {
  method: 'POST',
  headers: {
    'Authorization': 'Bearer YOUR_API_KEY'
  },
  body: body
})
.then(response => response.text()).then(srt => {
  // Ready-to-use SubRip subtitle file
  console.log(srt);
})
.catch(error => {
  console.error('Error:', error);
});
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Frequently Asked Questions

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Other APIs: Speech-to-Text API, Whisper API, Speaker Diarization API, DeepSeek API