youtube-transcript-api works locally but fails on the server: why, and how to fix it

You wrote a few lines with youtube-transcript-api,
tested them on your laptop, and every transcript came back. Then you deployed to AWS, Google Cloud, Azure,
Vercel, Render, Railway or a GitHub Actions runner, and the same code started failing on every video.

The symptom

Depending on the library version, you get one of these:

• RequestBlocked or IpBlocked in current versions
• TranscriptsDisabled on videos that clearly have captions, in older versions
• 429 Too Many Requests, or an XML parse error such as no element found

The giveaway is that the same video works from your machine and fails from the server.

Why it happens

YouTube blocks most IP addresses that belong to cloud providers. The library's own README says so in
Working around IP bans,
and issue #303 ("works locally, fails on Cloud machine")
gathered nearly 200 comments. Your code isn't wrong. The IP address it runs from is.

Even a home or office IP gets blocked for a while if it sends many requests in a short time.

Fix 1: rotating residential proxies in the library

The library supports proxies directly. Its README recommends rotating residential proxies, because YouTube
also bans static proxies after a while:

from youtube_transcript_api import YouTubeTranscriptApi
from youtube_transcript_api.proxies import WebshareProxyConfig

ytt_api = YouTubeTranscriptApi(
    proxy_config=WebshareProxyConfig(
        proxy_username="<username>",
        proxy_password="<password>",
    )
)
ytt_api.fetch("dQw4w9WgXcQ")

Any other provider works through GenericProxyConfig(http_url=..., https_url=...).

Good for: steady volume, when you want to keep everything in your own code.
Watch out for: you pay for proxy bandwidth, and you handle retries and IP rotation yourself. Datacenter
proxies are cheaper but get blocked just like cloud IPs.

Fix 2: fetch from a machine YouTube doesn't block

Run the fetching part from a home connection (an old laptop, a Raspberry Pi) and send the results to your server.

Good for: personal projects with low volume.
Watch out for: it doesn't scale, it's one more machine to keep running, and the home IP can be
rate limited too.

Fix 3: a hosted transcript API

Let a service run the requests through its own proxies and give you the result over HTTP.
Disclosure: I built one of these, the YouTube Transcript Scraper
on Apify. It takes video, playlist or channel links and returns text, timestamped segments, SRT or VTT:

from apify_client import ApifyClient

client = ApifyClient("<APIFY_TOKEN>")
run = client.actor("andracore/youtube-transcript-scraper").call(
    run_input={"urls": ["https://youtu.be/dQw4w9WgXcQ"], "outputFormat": "text"}
)
for item in client.dataset(run.default_dataset_id).iterate_items():
    print(item["title"], item.get("transcript") or item.get("error"))

It costs US$ 0.004 per transcript on the free plan (less on paid plans), with proxies included. Videos without
captions aren't charged, and the free plan's US$ 5 monthly credit covers about 1,250 transcripts. If you use an AI
agent, the youtube-transcript skill wraps the same call.

Good for: serverless functions, CI jobs and agents, or when you don't want to manage proxies.
Watch out for: you depend on a third party and pay per transcript.

Which one to pick

Whatever you choose, cache the transcripts you already have. Captions rarely change, and every request you
don't make is one fewer chance of getting blocked.