Test Visual Impact
See how your thumbnail stands out against competitors. What looks great in Photoshop might blend in on YouTube.
Why Preview Your YouTube Thumbnails?
Your thumbnail is the first thing viewers see. Make sure it stands out in every YouTube layout before you hit publish.
Mobile-First Preview
70%+ of YouTube views come from mobile devices. Ensure your thumbnail text is readable on smaller screens.
Boost CTR by 154%
Studies show optimized thumbnails can increase click-through rates dramatically. Preview to perfect.
Search Optimization
Thumbnails appear differently in search vs. home feed vs. sidebar. Test all views before publishing.
YouTube Thumbnail FAQs
What is the ideal YouTube thumbnail size in 2024?
The recommended YouTube thumbnail size is 1280×720 pixels with a 16:9 aspect ratio. The minimum width is 640 pixels, and the maximum file size is 2MB. YouTube supports JPG, GIF, and PNG formats. For best quality, always use the maximum resolution.
How does this free thumbnail previewer work?
Simply drag and drop your thumbnail image (or click to upload). Instantly see how it will appear across four different YouTube layouts: home feed, search results, recommended sidebar, and mobile app. Your thumbnail is displayed alongside real YouTube video mockups for accurate comparison.
Is this YouTube thumbnail previewer really free?
Yes, this YouTube thumbnail previewer is 100% free with no limits. Test as many thumbnails as you want. No account required. Your images are processed entirely in your browser—they're never uploaded to any server, ensuring complete privacy.
Why do thumbnails look different on mobile devices?
Mobile thumbnails appear much smaller than desktop versions—sometimes 70% smaller. Small text, fine details, and subtle elements become unreadable. That's why professional YouTubers use large, bold text and high-contrast images. Use our mobile preview to test readability before publishing.
How can I make my YouTube thumbnails stand out?
Great thumbnails use: (1) High-contrast colors that pop against YouTube's white/dark backgrounds, (2) Large, readable text limited to 3-5 words, (3) Expressive faces showing emotion, (4) Clean, uncluttered compositions. Use this previewer to test your thumbnail against competing videos in the home feed.
Need help creating stunning thumbnails?
Try Stumbnail's AI Thumbnail Generator