Leaf & Spine

5.25 x 8 in · 310 pages

310-page 5.25 x 8 in book: spine width & cover size

A 310-page 5.25 x 8 in paperback has a spine of 0.6981 in (17.73 mm) on white paper or 0.775 in on cream. Full cover with bleed: 11.448 x 8.25 in.

0.698 inSpine, white paper17.73 mm
0.775 inSpine, cream paper19.69 mm
11.45 x 8.25Full cover, inchesincl. bleed
329 gEstimated weight11.6 oz

Cover template (white paper)

Barcode areaBACK COVER5.25 x 8 inFRONT COVER5.25 x 8 inSPINE 0.698 inFull cover 11.448 x 8.25 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 ink0.6981 in17.73 mm11.448 x 8.25 in290.8 x 209.6 mm3,434 x 2,475 px
Cream paper, black ink0.775 in19.69 mm11.525 x 8.25 in292.7 x 209.6 mm3,458 x 2,475 px
Standard color (white)0.6981 in17.73 mm11.448 x 8.25 in290.8 x 209.6 mm3,434 x 2,475 px
Premium color (white)0.7276 in18.48 mm11.478 x 8.25 in291.5 x 209.6 mm3,443 x 2,475 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)0.8857 in22.5 mm
400 PPICream book paper (~55 lb)0.775 in19.69 mm
444 PPIWhite book paper (~50 lb)0.6982 in17.73 mm
500 PPILightweight text (~45 lb)0.62 in15.75 mm
600 PPIThin text (~40 lb)0.5167 in13.12 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 11.448 x 8.25 in — or 3,434 x 2,475 px at 300 ppi.
  • The back cover runs from the left edge to 5.375 in; the spine from 5.375 to 6.073 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)
250 pages0.563 in0.625 in11.313 x 8.25 in
260 pages0.5855 in0.65 in11.336 x 8.25 in
270 pages0.608 in0.675 in11.358 x 8.25 in
280 pages0.6306 in0.7 in11.381 x 8.25 in
290 pages0.6531 in0.725 in11.403 x 8.25 in
300 pages0.6756 in0.75 in11.426 x 8.25 in
320 pages0.7206 in0.8 in11.471 x 8.25 in
330 pages0.7432 in0.825 in11.493 x 8.25 in
340 pages0.7657 in0.85 in11.516 x 8.25 in
350 pages0.7882 in0.875 in11.538 x 8.25 in
360 pages0.8107 in0.9 in11.561 x 8.25 in
370 pages0.8332 in0.925 in11.583 x 8.25 in

310 pages in other trim sizes

TrimSpine (white)Full cover (white)
5 x 8 in0.6981 in10.948 x 8.25 in
5.06 x 7.81 in0.6981 in11.068 x 8.06 in
5.5 x 8.5 in0.6981 in11.948 x 8.75 in
6 x 9 in0.6981 in12.948 x 9.25 in
6.14 x 9.21 in0.6981 in13.228 x 9.46 in
6.69 x 9.61 in0.6981 in14.328 x 9.86 in
7 x 10 in0.6981 in14.948 x 10.25 in
7.5 x 9.25 in0.6981 in15.948 x 9.5 in
8 x 10 in0.6981 in16.948 x 10.25 in
8.5 x 8.5 in0.6981 in17.948 x 8.75 in
8.5 x 11 in0.6981 in17.948 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 310-page 5.25 x 8 in book?
On white paper it is 0.6981 in (17.73 mm); on cream paper 0.775 in (19.69 mm), using KDP's per-page factors.
What size should the full cover be?
For white paper: 11.448 x 8.25 in (290.8 x 209.6 mm) including 0.125 in bleed on every side. For cream paper: 11.525 x 8.25 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 310-page 5.25 x 8 in paperback?
About 329 g (11.6 oz) on white paper with a standard cover — useful for estimating postage.