creative · free Companion App · local in this browser
Book Spine Width
Turn page count, paper caliper, and a cover allowance into a spine width.
Enter your numbers
Enter only the details needed for this task. Check them against the original source.
Now set to . The result, the chart, and the meter follow the slider as you drag. Typing a number in the form above moves the slider to match.
Your result
Your result will appear here.
Engine self-test
Running golden cases…
Result chart
The bars are drawn from the numbers in your result and redraw on every compute. They show no new information and store nothing.
The chart is drawn from your result by this page's script. The text result above carries the same numbers.
Source notes
- International Organization for Standardization (ISO) / printing industry standards — Resolution for print output
300 pixels per inch is standard for high-quality print viewing at close range; large posters viewed from further away can use lower PPI.
Reviewed 2026-10-26. Viewing distance, printer, and paper stock change acceptable resolution.
What this App does not do
This App multiplies the caliper you enter. It does not replace a printer template or a physical proof.
This free App has no paid features. It does not contact an agency, employer, bank, seller, provider, or other person.