D4Y.online REST API for Developers — Download Videos Programmatically

D4Y.online now offers a public REST API that lets developers download videos from 20+ platforms programmatically — no browser required. Whether you are building a media archiver, a content pipeline, a research tool, or any application that needs to save online videos, the API gives you full control. To get started, create a free account at d4y.online/register. After logging in, go to d4y.online/developer and click Generate My API Key. Your key is a UUID that authenticates all API requests via the X-API-Key header. The API has three core endpoints. POST /api/v1/developer/download accepts a JSON body with a url (required), quality (best, 4k, 1080p, 720p, 480p — default best), and format (mp4 or mp3 — default mp4). It immediately returns a task_id. Use GET /api/v1/developer/status/{task_id} to poll the download status — the response includes the current status (queued, analyzing, downloading, complete, or error), progress percentage, download speed, and ETA. When status is complete, call GET /api/v1/developer/file/{task_id} to retrieve the file as a binary stream. Files are stored for 6 hours after completion. Every free API key includes 100 requests per day. The daily counter resets at midnight UTC. You can revoke and regenerate your key at any time from the developer page. All endpoints require authentication — requests without a valid X-API-Key header return 401 Unauthorized. Here is a complete Python example: import requests; API_KEY = 'your-api-key'; r = requests.post('https://www.d4y.online/api/v1/developer/download', headers={'X-API-Key': API_KEY}, json={'url': 'https://youtube.com/watch?v=dQw4w9WgXcQ', 'quality': '720p'}); task_id = r.json()['task_id']. Then poll /developer/status/{task_id} in a loop until status equals complete, then download /developer/file/{task_id}. The API supports all platforms available on the main site: YouTube, TikTok, Instagram, Facebook, Twitter/X, Twitch, Vimeo, Reddit, SoundCloud, Dailymotion, Pinterest, LinkedIn, Bilibili, Rumble, Kick, Odysee, and more. MP3 extraction works by setting format to mp3. The API is HTTPS-only and rate-limited per key. Register at d4y.online to get your key and start building today.