YouTube captions are a goldmine of text data. They power AI applications, accessibility tools, content analysis, and search features. But accessing them programmatically has always been harder than it should be. This comprehensive guide covers everything developers need to know about the YouTube Captions API, from basic extraction to advanced batch processing and AI-powered transcription.
Understanding YouTube Caption Types
YouTube has three types of captions: manual (uploaded by creators, highest accuracy), auto-generated (created by YouTube's speech recognition, variable quality), and community-contributed (created by viewers, being phased out). When using YouTubeTranscripts.co, we automatically select the best available caption track, preferring manual over auto-generated.
API Authentication
Authentication is a single API key passed in the x-api-key header. No OAuth, no tokens, no refresh flows.
# Every request uses the same simple authentication
curl -H "x-api-key: YOUR_API_KEY" \
"https://api.youtubetranscripts.co/v1/transcript?url=VIDEO_URL"Response Format
The API returns JSON with the video metadata and an array of transcript segments.
{
"title": "Video Title",
"channel": "Channel Name",
"duration": 600,
"transcript": [
{
"text": "First sentence of the video",
"start": 0.0,
"duration": 3.5
},
{
"text": "Second sentence continues here",
"start": 3.5,
"duration": 4.2
}
]
}Output Formats
The API supports three output formats via the format parameter: default (timed segments array), text (full transcript as a single string), and srt (SRT subtitle format). Choose the format that fits your use case.
import httpx
API_KEY = "YOUR_API_KEY"
URL = "https://youtube.com/watch?v=VIDEO_ID"
# Timed segments (default)
segments = httpx.get(f"https://api.youtubetranscripts.co/v1/transcript?url={URL}",
headers={"x-api-key": API_KEY}).json()
# Plain text
text = httpx.get(f"https://api.youtubetranscripts.co/v1/transcript?url={URL}&format=text",
headers={"x-api-key": API_KEY}).json()
# SRT subtitles
srt = httpx.get(f"https://api.youtubetranscripts.co/v1/transcript?url={URL}&format=srt",
headers={"x-api-key": API_KEY}).json()Language Selection
Specify a language code to get captions in a specific language. If the requested language is not available, the API falls back to the default language.
# Spanish captions
resp = httpx.get(
"https://api.youtubetranscripts.co/v1/transcript",
params={"url": VIDEO_URL, "lang": "es"},
headers={"x-api-key": API_KEY},
)Error Handling Best Practices
The API uses standard HTTP status codes. Handle common errors like invalid URLs (400), authentication failures (401), rate limits (429), and server errors (500).
import httpx
try:
resp = httpx.get(
"https://api.youtubetranscripts.co/v1/transcript",
params={"url": video_url},
headers={"x-api-key": API_KEY},
)
resp.raise_for_status()
data = resp.json()
except httpx.HTTPStatusError as e:
status = e.response.status_code
if status == 400:
print("Invalid YouTube URL")
elif status == 401:
print("Invalid API key")
elif status == 404:
print("Video not found or private")
elif status == 429:
print("Rate limited, retry later")
else:
print(f"Server error: {status}")Conclusion
The YouTube Captions API from YouTubeTranscripts.co covers every use case: single video extraction, batch processing, multiple formats, language selection, and AI fallback. The API is designed to be simple enough for a quick script and robust enough for production applications. Get your API key and 150 free requests at youtubetranscripts.co.
Ready to start extracting YouTube transcripts?
Get 150 free API requests. No credit card required.
Get Your Free API Key