Option A
Free preview lab
Compare YouTube thumbnails and titles before publishing
Compare 2 to 6 thumbnails and titles before publishing. Get an explainable preflight score, a relative ranking, and the first fix for every option. No login required.
Images stay in your browser. Report sync is optional and in beta.
Test setup
Revision draft
Saved reports use downsized previews. Replace any thumbnail you changed before comparing again.
How the score is calculated
CoverA canvas reads saturation, contrast, warm-color ratio, brightness, and skin-tone ratio, then maps those into five visual dimensions. These are heuristics, not a read on what real viewers will do.
TitlePulls from seven angles: hook, emotion, conflict, length, structure, keywords, and readability.
Relative rankingCombines the cover and title scores into a 0 to 100 preflight score. It compares this set only and does not estimate your channel's real CTR.
Example of the result card you will get
53%
Lift cover contrast to sharpen the focal subject.
Upload thumbnails to see your result here
The tool analyzes images locally in your browser. Compare 2 to 6 thumbnails and titles, then save the report only if you want history.
Use the score for the edit, then validate with real viewers
Follow the pre-publish workflow to turn the ranking into a shortlist. Check the scoring method when you need to understand a result, then use a live audience test to see how viewers respond.
Did this result help you narrow down what to test next?
This feedback does not include your thumbnails, titles, score, or account details.
Preflight ranking
Finalist context preview
See how the top three pairs read when the thumbnail and title are reduced.
This checks size and readability. It is not a YouTube viewer test or a pixel-perfect copy of YouTube.
Score breakdown
10,000-iteration preference model
What to fix first
Pre-publish workflow
How it works
Drop in 2 to 6 covers + titles
Upload a static JPG, PNG, or WebP from your device. Each image can be up to 16 MB; original files stay local for scoring.
Get a 12-dimension score breakdown
Each pair gets a 0 to 100 preflight score across 5 visual and 7 title dimensions, then a repeatable preference model ranks the set.
Shortlist the best candidates
Use the relative lead and focused fixes to narrow your set, then validate your final 3 with YouTube's real audience test.
What each output means
Every number below is a relative preflight signal for this set. None of it measures your audience or your real YouTube click-through rate.
- Preflight score
- The cover and title scores are averaged into a 0 to 100 relative score. It is useful for comparing this set, not predicting your channel's CTR.
- Relative ranking
- The options are ordered by their preflight scores. A lead means the model prefers one option inside this set, not that viewers will.
- Score breakdown
- Five cover dimensions (saliency, emotional pull, color quality, composition, readability) and seven title angles. Each is a heuristic score, not a viewer verdict.
- 10,000-iteration model
- A deterministic visualization that repeatedly samples the same preflight scores. It adds no audience evidence and never sees your channel.
- Fix list
- The weakest dimension on each variant, surfaced first so you know where to spend your edit time before you publish.
- Grade (A to F)
- A heuristic band over the combined score, with cutoffs at 80, 65, 50, and 35. A high grade means the cover and title do their mechanical job, not that the video will perform.
What this tool is not
- Not a test on real viewers. It scores pixels and text, not people.
- Not a measurement of real CTR. YouTube Studio is the only source of truth for your real click-through rate.
- Not a replacement for YouTube's Test & Compare. We run a heuristic preflight before you publish; YouTube tests after, using real watch data.
- Not able to see your real audience. No OAuth, no extension, no channel access, and no view of your live video, ever.
Thumbnail test FAQ
Short, honest answers about what the tool does and does not do.
How many thumbnails can I compare at once?
Up to 6 today. Drop in anywhere from 2 to 6 cover and title pairs and the scorer ranks all of them in a single run.
What image file types are supported?
Static JPG, PNG, and WebP files. Each image can be up to 16 MB and 20 megapixels. A comparison can use up to 48 MB and 60 megapixels. Files stay in your browser for scoring.
Does this touch my live YouTube video?
No. This is a pre-publish creative preflight. It never connects to your YouTube channel, asks for no OAuth, and cannot see or change any video you have already published.
Are my thumbnails uploaded anywhere?
Core scoring runs in your browser. Account sync sends a downsized preview plus title and score data only after sign-in and an explicit save.
Do I need to log in?
Not for the core test. Open the page and run a comparison without an account. A free beta account can sync reports you choose to save across devices.
How long does a test take?
Scoring runs on your device, so the time varies with its performance and the size of the images. The result appears in the same session once every image has been read and scored.
Can I test the title and the thumbnail together?
Yes. Each variant is one cover plus one title, scored as a single unit, because that is how viewers see them in the feed.
What does Grade A mean?
Grade is a heuristic band (A, B, C, D, F at 80, 65, 50, 35) over the combined cover and title score. A high grade means the cover and title do their mechanical job of grabbing attention and reading clearly. It is not a promise of real YouTube performance.