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YouThumb: YouTube Thumbnail Tester & Generator

Test thumbnails in the real YouTube feed and generate new ones. Preview, score, enhance and improve your CTR before you publish.

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Time on the storeUnder a yearA rough range, not an exact date

Store users139As shown on the Chrome Web Store

Chrome Web Store rating5.0 / 57 ratings on the Chrome Web Store

Last store update17 Jun 2026Version 1.1.0, 4 months ago

Inside the extension

YouThumb: YouTube Thumbnail Tester & Generator developer product preview 1

Product image 1 of 3

Reviews

PUCHKA G.P5 months ago
This tool definitely makes life easier... All you do is upload your title and Thumbnail and it matches with other 6 competitors and gives you the best thumbnail improvement suggestions... Even I couldn't believe my thumbnail after following its instructions... HIGHLY RECOMMENDED !!!
Jaime Bolton6 months ago
love this as a content creator, the live thumbnails are especially useful in the live feed, helps with alignment
Aleajandrona6 months ago
I didn’t expect this to be that useful, but seeing my thumbnail in the actual YouTube feed kinda blew my mind. Makes it way easier to spot what works.
neamonyn O6 months ago
Seeing my thumbnail next to actual competing videos before publishing is kind of crazy. I’ve already scrapped a few designs that I thought were good but clearly weren’t.
Dženan Ahmetspahić8 months ago
I've been using YouThumb Tester for a couple of weeks now. The developer is very responsive, takes criticism seriously and truly works on improving the extension. It's about what you expect - the core of the extension is to check your video's thumbnail and title within context of your own YouTube home page, or a search results page, along with the rest of your organic recommendations. This in turn is useful because the content I consume and the content I make live within the same larger target group, so seeing my title and thumb within context means a lot. There are some bugs, where I'd need to refresh the page I'm currently on before the extension takes those changes into context, or it sometimes working wonky with other Chromium-based browsers, but otherwise it works just fine. I'd recommend it wholeheartedly to any content creator even if you don't have a need for the AI features. The AI features, however, add to the experience and allow you to check the rating of your thumbnail within context of your niche. Yes, it's still a clanker telling you if your thumbnail is good, but it's also useful for early in your YouTubing journey. Try it yourself
Nejira Aličajić9 months ago
Helpfull extension to check instantly how my thumbnail looks in feed. Simple...

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Permissions & access

Access levelMedium

Can ask for your Google account sign-in, plus 1 more sensitive permission.

What it’s allowed to do, not what it actually does. Not a safety rating.

Permissions 4

Sensitive2

Ask for your Google account sign-inidentity
See the address and title of every open tabtabs

Standard2

Work on the tab you click it onactiveTab
Save its own settingsstorage

Members also see when a new version asks for new access.

Website access 16

www.youtube.com
www.googleapis.com
accounts.google.com
firestore.googleapis.com
firebaseio.com and its subdomains
firestore.googleapis.com and its subdomains
identitytoolkit.googleapis.com
securetoken.googleapis.com
firebaseapp.com and its subdomains
googleapis.com and its subdomains
us-central1-aiplatform.googleapis.com
us-east1-aiplatform.googleapis.com
us-west1-aiplatform.googleapis.com
europe-west1-aiplatform.googleapis.com
asia-east1-aiplatform.googleapis.com
api.youthumb.online

Extension ID: jkeenlkhgffffnmbpeniapfnehkpiphd
Package size: 212KiB
Manifest: Version 3

The maker

This is the only listing we know of from This maker.

Listings: 1
Combined store users: ≈139
Store Featured: 1

Combined users can count the same person more than once. Maker profile

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One research report for YouThumb: YouTube Thumbnail Tester & Generator. Reports come with Plus, Pro and Max.

Takeaway & demandCited takeaway and search volumes
Traffic & domainPopularity rank, visits and authority
Money & pricingPlans and prices from the maker’s site
ReviewsComplaints and praise, quoted
Competitors & ranksRank against the closest listings
Build opportunityWhat to build and how to position it

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Inside the extension

Reviews

Reviews

Competitors

Permissions & access

Permissions 4

Sensitive2

Standard2

Website access 16

The maker

Should you build in this niche?

Reviews