Publishing glossary

Book block: the interior pages before the cover.

The book block is the trimmed stack of interior pages that the cover wraps around.

Checked:

Block thickness equals spine widthSet by page count and paperInterior file defines the block

Why the book block matters

The block's thickness is exactly what the cover spine wraps around. If interior page count changes after the cover is built, the spine no longer fits.

  • Finalize pagination before the cover
  • Thicker paper makes a thicker block
  • Premium color adds thickness too

Keeping block and cover in sync

Use the cover calculator with the final page count, and re-run it after every interior change so the wrap always matches the block.

FAQ

Frequently asked questions

What is inside a book block?

The printed interior pages, front matter through back matter, trimmed to the final page size.

Does the cover calculator use the book block?

Yes. Spine width is the block thickness, derived from page count and paper type.

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