Русский
EnglishYouTube thumbnail tester
See how your thumbnail looks in the YouTube feed next to other videos – on Home, in Search, in Up next, on mobile and in Shorts.
The tester runs right in your browser – turn on JavaScript to use it.
Three steps to an honest check
Add your thumbnail
Drop a file, paste it from the clipboard or give a video link – the tester will grab its current thumbnail.
Type the title
Thumbnail and title work together. The mockup cuts the title off the way the YouTube feed does.
Compare with neighbors
Switch between Home, Search, Up next, mobile and Shorts. Shuffle the neighbors and look again.
What to look for in the feed
Viewers decide in a split second and see your thumbnail small. Go through this list right in the tester.
- It’s clear at a glance what the video is about – even at the small Up next size
- The text is readable on a phone: 2–4 big words, not a sentence
- Nothing important sits in the bottom-right corner – that’s where the video length goes
- In Squint mode one main spot stands out: a face, an object or a word
- In black and white the subject still separates from the background
- The thumbnail and the title complement each other instead of repeating
- It stands out equally on the light and dark themes
More free tools
No sign-up and nothing to install – everything runs in your browser.
What creators say about Bloggers.tools
Saves what matters most – time
I’ve been a successful YouTuber since 2016. Bloggers.tools helps me a lot in my work and, most importantly, saves time. I especially recommend the subscription with title, description and timestamp generation.
Works without glitches
I’m an SEO specialist with over 20 years of experience and the founder of Rush Agency. Everything I’ve used here is convenient, affordable and – what matters to me as a practitioner – works without glitches.
Help on the first request
A reliable service! They help on the very first request and answer questions really fast. Thanks to the founder!
Tested a thumbnail here?
Tell us whether the tester helped you pick a thumbnail – we’ll publish your review on the site.
Write a review →Frequently asked questions
Everything about the thumbnail tester: how it works, what it shows and how to pick a thumbnail that stands out in the feed.
Does the tester upload my image to a server?
No. The thumbnail opens right in your browser and isn’t sent anywhere. It’s gone once you close the page.
Is this an exact copy of YouTube?
It’s a mockup: proportions, rounded corners, the length badge and title truncation match the YouTube feed. YouTube updates its design regularly, so small details may differ – but it’s plenty for comparing thumbnails side by side.
Can I test a vertical thumbnail for Shorts?
Yes. Upload a 9:16 image and the tester switches to Shorts automatically.
Why does a badge cover the bottom-right corner?
That’s where YouTube shows the video length. Keep text and key details out of it – turn on “What YouTube covers” to see every such zone.
What do “Squint”, “B&W” and “Light theme” do?
“Squint” blurs the feed the way a quick glance does: one main spot should remain – a face, an object or a word. “B&W” removes color: if the subject blends into the background, the thumbnail relies on color alone. “Light theme” shows the feed the way viewers with YouTube’s light appearance see it. “Shuffle” moves your thumbnail to a new spot among the others, and “Find mine” highlights it for a second.
How do I compare my thumbnail with a competitor’s?
Paste a link to the competitor’s video – the tester grabs its current thumbnail. To save it in a specific size, use the thumbnail downloader.
Is the tester free?
Yes, it’s free with no sign-up – everything runs right in your browser.
Does the tester predict CTR?
No, and we don’t make up forecasts. YouTube Studio shows the real CTR after you publish. The tester helps you see the thumbnail through a viewer’s eyes beforehand.
How do I find out which thumbnail performs best?
YouTube Studio on desktop has a built-in A/B test: up to three thumbnails and titles on one video. YouTube shows them to different viewers and keeps the one with the most watch time – not the highest CTR. A test runs for up to two weeks and needs advanced features; it isn’t available for Shorts. The tester helps you shortlist options for that test.
What thumbnail size does YouTube need?
For regular videos: 16:9, at least 640 px wide. YouTube recommends uploading thumbnails as large as possible, up to 3840×2160. See every requirement in the thumbnail size guide.
How do I check a thumbnail from the Bloggers.tools generator in the feed?
In your dashboard, open the menu of a finished thumbnail (three dots) and choose “Check in the feed” – the tester opens in a new tab with that thumbnail and the video title already in place. To make a new thumbnail around the video’s content, use the thumbnail generator – 1 thumbnail is free to try.
Thumbnail not catching the eye? Make a new one
The generator reads the video’s full subtitles and builds a thumbnail around its content – 16:9 for videos or 9:16 for Shorts in 3–5 minutes.
Our other services
Everything a creator needs to grow, monetize and work with brands.
Free tools: YouTube thumbnail downloader · YouTube thumbnail size · download your own video
Ask AI how to make your thumbnail stand out
Ask AI assistants what to look for in the feed and how to stand out from the videos around yours. Pick an assistant – it opens with the question ready.