Does your cover make readers stop?
Your cover decides whether a browsing reader clicks, usually at thumbnail size on a phone. Describe your cover and get a graded report card on how well it sells, with the specific changes that would help most.
What the cover grader scores
Your cover is scored from 0 to 10 on six things: genre fit (does it look like the books your readers already buy), thumbnail readability (does it still work when it is stamp-sized on a phone), title legibility and placement, the central image or concept, typography and font hierarchy, and professional finish. Each score comes with a short verdict and one concrete fix, and the six scores are averaged into an overall mark out of 100 with a letter grade.
How to read your score
Most real covers land between 4 and 7 on each dimension, so a middling score is normal and useful, not a failure. Look for the lowest bar first. A cover that scores well on imagery but poorly on genre fit or thumbnail readability usually needs a rethink of the layout rather than a new illustration, because readers skim past a cover that does not signal its genre in the first second.
What to fix first
Start with the three priority fixes at the bottom of the report. They are ordered by impact. Genre signals and title size at thumbnail scale tend to matter more than finer details like texture or colour grading. Describe your revised cover and grade it again to check the change helped. When you are ready to design, the cover tools inside CruxOne let you generate and adjust a cover in the same place you write and publish the book.
Frequently asked questions
What makes a book cover sell?
Signalling the genre instantly at thumbnail size. Readers judge by whether a cover looks like the books they already love, so fitting your genre's conventions matters more than looking unique.
Can you grade a cover from a description?
Yes. This tool grades the cover concept, genre fit, title placement, imagery and typography, from your description. It is a fast way to catch problems before you finalise the design.
Is the cover grader free?
Yes, with a few grades a day and no signup to see your result. An account raises the limit and lets you generate a new cover in CruxOne.
Why does thumbnail size matter so much?
Most book discovery happens on phones, where your cover is stamp-sized. If the title is not legible and the image is not clear at that size, the cover fails.