How many pages is 90,000 words?

Three hundred sheets means 150 sheets of paper folded into signatures, a block that ships as a parcel rather than a letter. That physical fact drives everything downstream: printing at $4.60, postage that grows with weight, and a spine of 0.6756 in that a binder can square without cracking the glue.

Pricing scales differently at this size. A $16.99 list price in the 60% band returns $5.59 a copy against $4.60 of printing, so the percentage margin is thinner than a 100-page book at $9.99: cost per sheet is fixed while the cover price is expected to stay reasonable. A $14.99 price returns $4.39, which is why long fiction lives or dies around a $15–$17 list.

The 828-page ceiling arrives at about 248,000 words, so 90,000 is safe; compilations are not. A collected edition of three 90,000-word titles reaches 900 pages and the upload is refused. The fix is either to publish each part separately — 300 pages apiece — or to reset the collection in a wider trim where the same text fits under 700 pages.

Proofs are the hidden arithmetic. KDP prints author copies at cost plus postage, so a 300-page proof costs $4.60 before shipping, and a box of twenty costs $92 against $46 for a 100-page novella. Proofing takes longer too: 300 pages at a page a minute is five hours of reading before the typos surface.

One related limit. Colour interiors cap at 600 pages on this platform, so a colour edition of a 90,000-word typescript cannot be published as a single block at 6×9 — the black-and-white version is the only one that fits, which is also why illustrated editions of long books are split by part.

Page count also widens the gutter. KDP asks for a half-inch inside margin up to 300 pages and five-eighths from 301, so a 300-page block sits exactly on the last comfortable step: add two pages and the text column either narrows or the typescript grows again. Typesetters plan for that break the way they plan part openers — it changes the measure, the line count and sometimes the page count itself.

Stock choice becomes visible at this thickness. Strong light shows the reverse of the next leaf through white paper on a three-100-page block; cream stock hides show-through better but is thicker, adding roughly 0.07 in to the spine. Neither option changes the word count, and both change what the finished object feels like in a reader’s hands.