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congcong
congcong

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I built a free YouTube thumbnail downloader + cover enhancer (no login, runs in your browser)

I wanted a dead-simple way to grab YouTube thumbnails in full resolution and turn them into custom covers—without signing up, without watermarks, without leaving the browser. So I built ThumbGrab.

What it does

1. Download any thumbnail in every resolution
Paste a YouTube URL, and you get all five sizes at once:

  • maxresdefault (1280×720 HD)
  • sddefault (640×480)
  • hqdefault (480×360)
  • mqdefault (320×180)
  • default (120×90)

If maxres doesn't exist (creator didn't upload a custom thumbnail), it auto-falls back to the next best quality.

2. A built-in Cover Enhancer
This is the part I'm proud of. Reusing a raw thumbnail verbatim isn't great for SEO because it's already indexed by Google. So ThumbGrab lets you:

  • Add your own title text
  • Pick a brand color
  • Apply a gradient mask (top/bottom/center)
  • Export a 1280×720 PNG that's unique and on-brand

All rendered on a <canvas> in real time.

3. Pulls video info via oEmbed
Title, channel name, avatar—fetched from YouTube's oEmbed endpoint via noembed.com (for CORS). No API key, no quota.

How it's built

  • Single static HTML file, ~44KB
  • Pure vanilla JS + Canvas 2D API
  • Hosted on Cloudflare (free tier)
  • Zero backend, zero tracking

The whole thing runs client-side. The URL you paste is processed in your browser; nothing is stored.

Try it

👉 youthumbdownloader.com

Feedback welcome—especially on the Cover Enhancer UX. What would make it more useful for your workflow?

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