REST API — Free Tier

D4Y.online Developer API

Download videos from 22+ platforms programmatically. Simple REST API, free tier included, no SDK required.

100 req/day free22+ platformsNo rate limit on pollingJSON responses

1Get Your Free API Key

API key is tied to your account. Log in or register — then generate a key with one click.

Requires login · One key per account · Free

Usage

Add to every API request:

X-API-Key: your-key-here

• 100 downloads/day (free tier)

• Resets at midnight UTC

• /status polling not counted

2Endpoints

POSThttps://www.d4y.online/api/v1/developer/keys

Generate API Key

Register your email and get a free API key. One key per email. Existing key is returned if already registered.

Request body

{
  "email": "[email protected]"
}

Response

{
  "key": "3f2a1b4c-...",
  "email": "[email protected]",
  "daily_limit": 100,
  "requests_today": 0
}
POSThttps://www.d4y.online/api/v1/developer/download Auth required

Submit URL for Download

Submit any supported video URL. Returns task_id immediately — download runs in background.

quality: best | 4k | 1080p | 720p | 480p format: mp4 | mp3

Request body

{
  "url": "https://youtube.com/watch?v=dQw4w9WgXcQ",
  "quality": "1080p",
  "format": "mp4"
}

Response

{
  "task_id": "abc123...",
  "message": "Download queued",
  "poll_url": "/api/v1/developer/status/abc123...",
  "file_url": "/api/v1/developer/file/abc123..."
}
GEThttps://www.d4y.online/api/v1/developer/status/{task_id} Auth required

Check Status

Poll this endpoint until status is complete or error.

status: queued → downloading → converting → complete | error

Response

{
  "task_id": "abc123...",
  "status": "downloading",
  "progress": 67,
  "filename": null,
  "speed": "2.3MB/s",
  "eta": "00:00:12",
  "error": null
}
GEThttps://www.d4y.online/api/v1/developer/file/{task_id} Auth required

Download File

Streams the completed file. Only available when status = complete. Files are kept for 6 hours.

Response

<binary file stream>

3Code Examples

# 1. Get API key
curl -X POST https://www.d4y.online/api/v1/developer/keys \
  -H "Content-Type: application/json" \
  -d '{"email":"[email protected]"}'

# 2. Submit download
curl -X POST https://www.d4y.online/api/v1/developer/download \
  -H "Content-Type: application/json" \
  -H "X-API-Key: YOUR_KEY_HERE" \
  -d '{"url":"https://youtube.com/watch?v=dQw4w9WgXcQ","quality":"1080p"}'

# 3. Poll status
curl https://www.d4y.online/api/v1/developer/status/TASK_ID \
  -H "X-API-Key: YOUR_KEY_HERE"

# 4. Download file
curl -L -o video.mp4 https://www.d4y.online/api/v1/developer/file/TASK_ID \
  -H "X-API-Key: YOUR_KEY_HERE"

4Supported Platforms

youtube.comyoutu.betiktok.cominstagram.comfacebook.comtwitter.com / x.comtwitch.tvvimeo.comsoundcloud.comreddit.comdailymotion.comtelegram.orgpinterest.comlinkedin.combandcamp.comthreads.netvk.combilibili.comrumble.comodysee.comkick.comxiaohongshu.com

Rate Limits & Fair Use

100 req/dayFree tier limit (resets UTC midnight)
UnlimitedStatus polling — never counted
6 hoursFiles kept after download completes

Need higher limits? Contact us at [email protected]