Ship the cover that actually wins the click.

Diagnose a cover at feed size, then run a live A/B for view deltas. Join the waitlist - or enter now with Founder Pack.

Be first when we open. No spam - launch only.

See the flow →

Sample head-to-head

One video · two covers · traffic split in the wild

Live
Winning thumbnail variant AAWinner
CTR0.00%
Views0
Challenger thumbnail variant BB
CTR0.00%
Views0
VS
Run your own test →

The cover you almost skipped might be the one that scales.

Evidence in, guesswork out

Score before you ship

Legibility, focus, and clutter in seconds - before the upload.

Thumbnail + title together

CTR is a pair. Test the combo, not isolated assets.

Traffic follows winners

Live A/B with smart allocation - more views on what works.

Private by default

Your channels and tests stay yours. Opt-in only for training.

Validation, not another tool pile

One flow from “which cover?” to “we know which one works” - AI first, real channel tests when you’re ready.

Diagnose at feed size

Legibility, focus, clutter, and contrast from the pixels in seconds - before you hit publish. Not a CTR guess.

AI Test on the channel

Rotate as many covers as you need. Included in the plan. We measure view-count change - YouTube does not give thumbnail CTR via API.

Pair thumbnails with titles

CTR is a combo, not a solo act. Spot when on-image text just restates the title.

The why, not a mystery score

Every Diagnose number comes with a reason you can check at 168×94. AI Test reports view deltas per window.

Seen at real feed size

Preview how it looks tiny on mobile, next to competing videos - not full-screen fantasy.

Built for weekly uploaders

Founder Pack is the live early-access SKU. Diagnose is free; AI Test slots come with the plan.

From draft to decision

Fast pre-publish signals when you need speed. Real A/B truth when you need certainty.

01

Bring a candidate

Upload a draft cover (title optional) or link a video from your connected channel.

02

Diagnose it

Get an explainable visual score at feed size, plus an attention map. Then rotate live when you need field truth.

03

Lock the winner

Ship the variant that gained views in its window, re-test older uploads, and keep a trail of what moved.

Get launch access first

Join the waitlist for ThumbnailTools - evidence-first thumbnail tools for creators who refuse to guess.

No spam. One email when we open.

Founder Pack is the live SKU.

Plans are locked in - checkout opens when we launch.

Questions, answered

Something sharp is on the way.

ThumbnailTools is almost ready. Evidence-first covers for creators who refuse to guess.

We’ll only email you at launch.