VidsTrackerYouTube thumbnail preview & A/B test
Upload your thumbnail, write your title and see exactly how it looks on YouTube: home feed, search results, suggested videos and phone, next to real videos. Add a B and C version and compare them.
How to use the YouTube Thumbnail Preview & A/B Test Tool
- Drop your thumbnail (1280×720) in the box, or paste it with Ctrl+V / Cmd+V.
- Write your title and your channel name. Add your channel picture if you want.
- Switch between Home, Search, Sidebar and Phone, in dark or light mode.
- Tap “Add version” to upload a B or C thumbnail and switch between them to see which one stands out.
Why preview a thumbnail before publishing?
A thumbnail never competes alone. On YouTube it sits next to a dozen other videos, often small, often on a phone. Seeing it in context shows you if the text is readable, if the face or object stands out, and if it looks different enough from everything around it.
What makes a thumbnail stand out
Few words in big letters, one clear subject, strong contrast with the feed (try both dark and light mode), and a reason to click that the title does not repeat. Check the phone view: most views come from phones, where thumbnails are smallest.
A/B testing on YouTube
YouTube lets you test up to three thumbnails on a published video with Test & Compare. Use this tool first to pick the strongest candidates, so the real test starts with good options.
Frequently asked questions
Is this thumbnail preview tool free?
Yes. It is free, with no sign-up and no limits.
Are my thumbnails uploaded anywhere?
No. Everything happens in your browser. Your images never leave your computer.
What size should a YouTube thumbnail be?
YouTube recommends 1280×720 pixels (16:9), under 2 MB, in JPG, PNG or GIF.
Can I compare two thumbnails?
Yes. Add up to three versions (A, B and C) and switch between them in the same feed.
Does it show how the title gets cut?
Yes. Titles are cut to two lines like on YouTube, so you can see if the important words fit.
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