ThumbnailScore
The guide explains what each metric means. This page shows the metrics doing something — two realistic packages taken apart, rebuilt, and rescored.
Case 1 · Thumbnail craft
A tutorial channel exports a thumbnail that looks fine on a 27-inch editing monitor: a full sentence of explanation across a screenshot of the software, plus a corner badge, plus an arrow. In the feed it renders about 168 pixels wide. At that size the sentence is a grey smudge, and three elements compete for a glance that lasts well under a second.
In your editor
In the feed (actual size) · 168px
A sentence, thin and mid-grey, over a busy screenshot. Nothing dominates.
In your editor
In the feed (actual size) · 168px
Three words, heavy, near-white on dark. One subject, one accent.
Same markup, same proportions — only the width changed. This is the size the decision actually gets made at.
Almost the entire gain came from one metric. Thumbnail readability is the heaviest single weight in the CTR layer, and it was the lowest score on the board — so it was the only change worth making first. The lesson is not "do these four things"; it is "fix your lowest heavy-weighted metric and re-measure before touching anything else."
Case 2 · The honest hook
A creator has learned that tension drives clicks, and pushes every lever at once: an all-caps shock title, a devastated expression, an implied catastrophe the video never actually delivers. Every curiosity metric goes up. The score goes down — and the reason is the most useful thing this tool will ever tell you.
I LOST EVERYTHING… (I'm done)
Creator · 128K views · 2 days ago
Maximum tension, minimum information. The video cannot pay this off.
Why I shut down my $40k/month channel
Creator · 128K views · 2 days ago
Still a real hook — but it promises exactly what the video delivers.
This is the case that justifies the whole scoring model. The hyped version wins on every pre-click signal and still scores 35, because the two layers are multiplied rather than averaged: a package that earns the click and loses the viewer is worth less than one that does both moderately well. If you only ever take one thing from this tool, take this — you are not optimising for clicks, you are optimising for clicks that survive.
Run your actual thumbnail and title through the analyzer, find your lowest heavily-weighted metric, change that one thing, and run it again. The gap between the two scores is the whole method.