Free 60-second cover audit. We render your cover at 90×135 pixels — the size Amazon shows on its mobile browse — and score legibility, resolution, aspect-ratio fit to KDP trims, greyscale contrast, edge safety and genre palette. No payment, no signup.
Amazon's mobile app displays your cover at roughly 90 by 135 pixels. Most covers that look brilliant in Canva or InDesign get destroyed at that size — title text vanishes, contrast collapses, edge content gets clipped. This audit catches every one of those failures.
Whether you've already published, are about to launch, or are still picking between three designs — running this first means you don't gamble your launch on a cover that won't convert in thumbnail.
"Will my cover pop at thumbnail size on Amazon?"
Need an NDA before uploading? Request a mutual NDA
Six rules. One render at the exact pixel size Amazon shows on mobile. Out of 100, with every failure flagged and a fix you can action.
The headline rule. We render the cover at Amazon mobile size and measure greyscale std-dev and Canny edge density to flag covers that collapse to mush in the carousel.
Pixel dimensions implying DPI at the closest standard book trim. 300 DPI = full marks. Anything under 200 fails on print.
Distance from 10 standard book trims (6×9, 5.5×8.5, 5×8, 8.5×8.5 picture-book, 7×10 cookbook etc.). Square or social-media ratios are penalised.
Per-genre brightness, warmth and saturation expectations across 13 genres. Thriller covers should read dark; romance should read warm and bright.
Does the cover still work in greyscale? Catches over-reliance on colour, which is the single most common cause of low thumbnail conversion.
Outer-5% variance check to detect content sitting too close to trim — text or faces likely to get clipped in the Amazon thumbnail crop.
One audit per stage of the publishing journey. All free. All take under 90 seconds.
Drop your manuscript PDF. We run the same 30+ checks Amazon does — margins, gutter, image DPI, font embedding, ToC links, blank pages, ISBN match. Out of 100.
Score my manuscript →Drop your Amazon URL. Cover at thumbnail size, title block on search, blurb opener, review base — out of 100 with a "ready / test small / not ready" verdict.
Run the scorecard →Live retrieval test against ChatGPT, Claude, Perplexity, Gemini and Amazon Rufus (simulated). Tells you what each model knows about your book — with web search active and from training alone.
Run the AI score →An AI-assisted editorial review of your manuscript — structure, prose quality, genre fit, pacing, hooks. The first-read every traditionally-published manuscript gets.
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