How the score is built
This scores each title on factors known to influence both click-through and searchability: length (titles around 40-60 characters avoid truncation in most views), the presence of attention-grabbing "power words," whether a number is included (list-style titles often draw clicks), and - if you give a target keyword - how early it appears in the title.
Why this is a heuristic scoring model rather than a click-through prediction
This is a heuristic scoring model based on common best practices, not a prediction of actual click-through rate or ranking - real performance depends heavily on your thumbnail, channel authority, and audience, which no title-only score can capture. Use the score to compare two titles' structural strengths against each other, not as a forecast of how many views either one will actually earn.
Why ALL CAPS titles get penalized rather than scored neutrally
A title written entirely in capital letters tends to read as spammy or desperate for attention to most viewers, which can hurt trust and click-through rather than help it, despite grabbing visual attention in a feed - the scoring reflects that known tradeoff by subtracting points specifically for all-caps titles, rather than treating capitalization as a neutral stylistic choice.
Why keyword placement is scored by how early it appears, not just whether it appears at all
A keyword appearing in the first third of a title is both easier for a scanning viewer to notice and more heavily weighted by search systems that favor early keyword placement - scoring early placement higher than a keyword buried near the end reflects that specific, well-documented difference rather than treating any mention of the keyword as equally valuable.