Book Size Calculator
Enter the page count, the paper colour and the trim size. The calculator gives the spine width, the full cover size with bleed and the pixel size for a 300 dpi cover file.
- Spine width
- Cover size
- Cover pixels
Use your printer's own template once the page count is final.
Spine width = pages × paper thickness. A 300 page 6 × 9 in book on white paper has a spine of about 0.676 in. The full cover with 0.125 in bleed is 12.926 × 9.25 in, or 3,878 × 2,775 pixels at 300 dpi.
Spine width chart
Typical print on demand paper. Search for pages.
| Pages | White (in) | Cream (in) | Colour (in) |
|---|---|---|---|
| 24 | 0.054 | 0.06 | 0.056 |
| 100 | 0.225 | 0.25 | 0.235 |
| 150 | 0.338 | 0.375 | 0.352 |
| 200 | 0.45 | 0.5 | 0.469 |
| 250 | 0.563 | 0.625 | 0.587 |
| 300 | 0.676 | 0.75 | 0.704 |
| 400 | 0.901 | 1 | 0.939 |
| 500 | 1.126 | 1.25 | 1.173 |
| 600 | 1.351 | 1.5 | 1.408 |
| 800 | 1.802 | 2 | 1.878 |
Inches.
Pages and spine
White paper, 6 × 9 in. Slide the pages.
The cover spread widens with the spine.
How to size a book cover
Pages to cover. Step through it.
Pages
Count.
Keep text 0.25 in inside the trim on every side.
White, cream or colour paper
Paper. Compare them.
Non-fiction.
Fiction.
Picture books.
Cream paper is slightly thicker, so the same book has a wider spine.
Before you design
Cover checks. Tick each item.
Tick each item as you go.
Export the cover as a PDF at 300 dpi.
What you get
Cover sizing. Each tile explains one result.
Width.
Full size.
At 300 dpi.
Thickness.
Spine advice.
Spine text needs about 100 pages or more to fit.
Frequently Asked Questions
No question matches that search.
How wide is a book spine?
The page count times the paper thickness.
How wide is the spine of a three hundred page book?
About two thirds of an inch on white paper.
What size is a book cover with bleed?
Twice the trim width plus the spine, plus an eighth of an inch on each side.
What is bleed?
Extra image past the trim line so no white edge shows after cutting.
Can I put text on a thin spine?
Only from about one hundred pages.
Is cream paper thicker than white?
Yes, slightly, so the spine is wider.
What resolution should a book cover be?
Three hundred dots per inch.
A cover that fits
Work out the spine and full cover size before you design and it wraps the book perfectly.
More size calculators
Each one has its own calculator, worked examples and answers to common questions.