The method

Diagnose. Remake. Predict. Prove.

Most thumbnail tools are a text box and a render button. This page explains what Rexels actually does with your channel, step by step, including the parts where we tell you we don't know.

The loop, end to end

Diagnose. Remake.
Predict. Prove.

01

Connect, read-only

Link YouTube in one click. Rexels pulls 90 days of real analytics: impressions, click-through, watch time. Read-only scopes, so nothing on your channel can be changed by us.

02

Diagnose

Every thumbnail is scored against your channel's own baseline, long-form and Shorts in separate cohorts. High-impression, low-CTR videos surface first: the ones a remake can actually help.

03

Remake

Regenerate from your actual video, in your visual language, with your real face. GPT-Image, FLUX, and Gemini do the painting; the brief comes from your data.

04

Predict

Candidates are ranked against the thumbnails that already won and lost on your channel, with the reasons spelled out. Too little history to call it? It says so instead of inventing a number.

05

Prove

Publish and watch the real numbers. Rexels keeps score on itself: it checks its calls against your realized click-through and shows the running accuracy on your channel.

Method

Measured, not vibes

Every thumbnail score you have seen was a language model's opinion. Ours is a measurement. Each candidate goes through the same instruments before anything is ranked.

Where the eye lands

Attention models trained on human gaze pick out the focal region, and how much of the image is fighting it.

Legibility at phone size

Every word of overlay text is read with its pixel geometry, then judged at the size a phone feed renders.

Clutter

A vision-science busyness measure on the shrunk image, because fine detail turns to mush at 120 pixels tall.

Subject presence

How much of the frame your face or subject actually owns, counted in pixels rather than guessed at.

Your visual fingerprint

A 1,024-number signature of each image, compared against the thumbnails that already won and lost for you.

Candidate B, measured
Faces detected
1
Subject share of frame
41%
Focal region
tight, centered
Overlay text
3 words, legible
Clutter
0.34 / 1
Similarity to winners
0.81
Predicted to beat 74% of your uploadsconf. high
Fig. 02 — one candidate's readout

Then Rexels checks its own work. The ranking is validated against your realized click-through, out of sample, and the running hit rate shows in the studio. When your history is too thin to call, you get not enough data: the one answer a vanity score will never give you.

For small channels

Too small to A/B test? That is exactly who this is for

Live testing needs thousands of impressions per variant. Below that, YouTube's own Test & Compare comes back Inconclusive, and so does every paid split tester. The tools built to fix low click-through do not work for the channels that need them most.

Rexels predicts before you publish, from your own history plus the visual evidence. A channel with twenty videos gets a calibrated call, not a coin flip. And once you are big enough to test live, Rexels hands its best candidate to YouTube's referee instead of pretending to be one.

The honesty contract

What we never do

No invented numbers

If a video is too new, too small, or your history is too thin to judge fairly, Rexels says "not enough data yet." A wrong number confidently delivered is worse than no number.

Relative, never absolute

Rexels never promises "this thumbnail will get 9% CTR." Click-through depends on topic, traffic source, and audience. What can be predicted honestly is which candidate is stronger for your channel, and that is exactly what we predict.

Read-only by default

Connecting your channel grants Rexels read-only scopes. We cannot upload, edit, comment, or swap anything. Every change to your channel is a change you make.

Graded in public

The prediction model is continuously validated against your realized results, out of sample, and the running hit rate is shown to you in the studio. When we are wrong, you see it before we explain it away.

The field

Where Rexels sits

Every tool here is good at its job. None of them close the loop from your analytics to a remade thumbnail to a measured result.

CapabilityRexelsAI generatorsChannel coachesA/B testersChat AIs
Generates the thumbnailsome
Reads your analytics, read-onlyduring tests
Tells you which videos to fixgeneric
Prediction calibrated to your channel
Works without live-test traffic
Real face, many reference photosbetaa fewa few
Measures real before-and-after CTRbeta
Reports its own accuracy
Admits when data is thin

AI generators: Pikzels, GoThumbnails. Channel coaches: vidIQ, TubeBuddy. A/B testers: ThumbnailTest, YouTube Test & Compare. Chat AIs: ChatGPT, Gemini. Public information as of mid-2026; if anything is out of date, tell us and we will fix it.

Named comparisons: vs Pikzels · vs vidIQ · vs ThumbnailTest

Ready to close the loop?

Connect your channel, read-only. See your worst thumbnails in minutes. Remake the first one today.

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