ThumbnailResizer

Resize YouTube Thumbnails in Seconds

Upload an image or paste a YouTube URL. Get the perfect size instantly — free, no sign-up.

Drop your thumbnail here

or click to browse

JPG · PNG · WebP · GIF

Or grab from YouTube

Supports 1280×720 · 640×480 · 480×360 · 320×180 and custom sizes

Every Format, One Tool

Resize thumbnails for YouTube, Instagram, Shorts, and more — all aspect ratios supported.

16:9 · YouTube HD
16:9 · YouTube HD

1280×720

1:1 · Square
1:1 · Square

1080×1080

9:16 · Shorts
9:16 · Shorts

720×1280

4:5 · Instagram
4:5 · Instagram

1080×1350

4:3 · Standard
4:3 · Standard

1024×768

21:9 · Ultrawide
21:9 · Ultrawide

2560×1080

Why Use ThumbnailResizer?

Built for YouTubers and content creators who need the right thumbnail size, fast.

Instantly resize to 1280×720 (HD), 640×480, 480×360, and 320×180 — the exact sizes YouTube recommends.

Everything You Need to Make Great Thumbnails

Simple, powerful tools for YouTubers and content creators.

YouTube URL Import

Paste any YouTube video URL and we'll fetch the thumbnail automatically.

Screenshot Beautifier

Place any screenshot on a beautiful gradient background with padding, shadow, and rounded corners — perfect for tech thumbnails.

Standard Size Presets

One-click presets for all YouTube-recommended thumbnail dimensions.

Batch Processing

Resize multiple thumbnails at once to save time on large projects.

AI Expand

Intelligently extend images to any aspect ratio using AI outpainting — no black bars.

Works in Your Browser

No software to install. Everything runs in your browser — fast and private.

Frequently Asked Questions

Have another question? Email us at support@thumbnailresizer.com

Resize Your YouTube Thumbnail Now

Free, instant, no sign-up required.

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