Leaf & Spine

8.5 x 8.5 in Square · 340 pages

340-page 8.5 x 8.5 in book: spine width & cover size

A 340-page 8.5 x 8.5 in paperback has a spine of 0.7657 in (19.45 mm) on white paper or 0.85 in on cream. Full cover with bleed: 18.016 x 8.75 in.

0.766 inSpine, white paper19.45 mm
0.85 inSpine, cream paper21.59 mm
18.02 x 8.75Full cover, inchesincl. bleed
619 gEstimated weight21.8 oz

Cover template (white paper)

Barcode areaBACK COVER8.5 x 8.5 inFRONT COVER8.5 x 8.5 inSPINE 0.766 inFull cover 18.016 x 8.75 in incl. 0.125 in bleed
Red: bleed (trimmed off) · dashed: 0.25 in safe zone · shaded: spine. Download a full-size template from the calculator.

Spine and cover by paper type

PaperSpineSpine (mm)Full cover (in)Full cover (mm)At 300 ppi
White paper, black ink0.7657 in19.45 mm18.016 x 8.75 in457.6 x 222.3 mm5,405 x 2,625 px
Cream paper, black ink0.85 in21.59 mm18.1 x 8.75 in459.7 x 222.3 mm5,430 x 2,625 px
Standard color (white)0.7657 in19.45 mm18.016 x 8.75 in457.6 x 222.3 mm5,405 x 2,625 px
Premium color (white)0.798 in20.27 mm18.048 x 8.75 in458.4 x 222.3 mm5,414 x 2,625 px

Per-page factors are those published by KDP; IngramSpark and offset printers use their own paper calipers.

Other printers: spine by paper PPI

Paper PPITypical stockSpineSpine (mm)
350 PPIBulky / heavy stock (~70 lb text)0.9714 in24.67 mm
400 PPICream book paper (~55 lb)0.85 in21.59 mm
444 PPIWhite book paper (~50 lb)0.7658 in19.45 mm
500 PPILightweight text (~45 lb)0.68 in17.27 mm
600 PPIThin text (~40 lb)0.5667 in14.39 mm

If your printer quotes pages per inch (PPI), spine = pages ÷ PPI. Ask for the exact PPI of your chosen stock.

Designing this cover

  • Build the cover canvas at 18.016 x 8.75 in — or 5,405 x 2,625 px at 300 ppi.
  • The back cover runs from the left edge to 8.625 in; the spine from 8.625 to 9.391 in; the front cover after that.
  • Spine text is allowed — centre it and keep 0.0625 in clear on each side.
  • Keep titles and faces at least 0.25 in inside the trim; KDP places the barcode in a 2 x 1.2 in area at the lower right of the back cover.
  • Export as a flattened PDF (PDF/X-1a is safest) with fonts embedded.

Nearby page counts

PagesSpine (white)Spine (cream)Full cover (white)
280 pages0.6306 in0.7 in17.881 x 8.75 in
290 pages0.6531 in0.725 in17.903 x 8.75 in
300 pages0.6756 in0.75 in17.926 x 8.75 in
310 pages0.6981 in0.775 in17.948 x 8.75 in
320 pages0.7206 in0.8 in17.971 x 8.75 in
330 pages0.7432 in0.825 in17.993 x 8.75 in
350 pages0.7882 in0.875 in18.038 x 8.75 in
360 pages0.8107 in0.9 in18.061 x 8.75 in
370 pages0.8332 in0.925 in18.083 x 8.75 in
380 pages0.8558 in0.95 in18.106 x 8.75 in
390 pages0.8783 in0.975 in18.128 x 8.75 in
400 pages0.9008 in1 in18.151 x 8.75 in

340 pages in other trim sizes

TrimSpine (white)Full cover (white)
5 x 8 in0.7657 in11.016 x 8.25 in
5.06 x 7.81 in0.7657 in11.136 x 8.06 in
5.25 x 8 in0.7657 in11.516 x 8.25 in
5.5 x 8.5 in0.7657 in12.016 x 8.75 in
6 x 9 in0.7657 in13.016 x 9.25 in
6.14 x 9.21 in0.7657 in13.296 x 9.46 in
6.69 x 9.61 in0.7657 in14.396 x 9.86 in
7 x 10 in0.7657 in15.016 x 10.25 in
7.5 x 9.25 in0.7657 in16.016 x 9.5 in
8 x 10 in0.7657 in17.016 x 10.25 in
8.5 x 11 in0.7657 in18.016 x 11.25 in

Spine width depends only on page count and paper; the cover width changes with the trim.

Frequently asked questions

How wide is the spine of a 340-page 8.5 x 8.5 in book?
On white paper it is 0.7657 in (19.45 mm); on cream paper 0.85 in (21.59 mm), using KDP's per-page factors.
What size should the full cover be?
For white paper: 18.016 x 8.75 in (457.6 x 222.3 mm) including 0.125 in bleed on every side. For cream paper: 18.1 x 8.75 in.
Can I put text on the spine?
Yes. KDP allows spine text only for books with more than 79 pages; keep it at least 0.0625 in (1.6 mm) from each spine edge.
How heavy is a 340-page 8.5 x 8.5 in paperback?
About 619 g (21.8 oz) on white paper with a standard cover — useful for estimating postage.