For writers
Free book tools.
Three quick tools for self-publishing authors — spine width, a page-count estimate, and trim sizes to scale. Free, no sign-up, mm and inches.
19.6 mm spine
Full cover wrap (W × H, incl. bleed)329.9 × 235.3 mm
Formula308 × 0.0025″/page
Wide enough for spine text (title + author). Keep a 1.6 mm safety margin from each fold.
Based on Amazon KDP paper specs. IngramSpark and other printers differ slightly — if you print on both, design to the narrower spine and keep spine text centred. Page counts round up to the nearest even number. Hardcover (case wrap) adds board thickness and a larger bleed — always confirm with your printer’s template.
Where to next
Plan the rest of your book
These help you plan. We make the real files.
When it’s time to build the interior, the spine and a print-ready cover, we prepare them precisely to your printer’s spec — with a fixed quote and a delivery date.
Want an exact spine and page count? Send us your manuscript for a fixed quote.