Tape the run, not the shelf
Measure upright to upright and subtract 25 mm for each divider. A nominal 1.83 m shelf works out at 1.80 m of usable run.
Shelf counts, order quantities
A 6-foot shelf with a 25 mm centre divider leaves 1.80 m of usable run — enough for roughly 60–95 trade paperbacks or 95–140 mass-market paperbacks. For stock quantities, order 1.5–2 times the copies sold in the same period last year and reorder when 2–3 weeks of average sales remain. The rest of this page is the working: formats, fit counts, print runs and ISBN checks.
01
What a trade paperback actually measures — 135 × 216 mm against the mass-market's 110 × 178 mm — with page bands and spine thickness for each format. The reference table is at /book-format-sizes.
02
The five sums that turn a taped shelf run into a fitting count and then into a purchase order, with the reorder point set in weeks. Worked through at /how-many-books-fit-on-a-shelf.
03
Print-run bands, jacket margins and the three second-hand price bands, in the order a buyer checks them. The routine is at /how-to-identify-a-first-edition.
Roughly 60–95 trade paperbacks or 95–140 mass-market paperbacks, on the 1.80 m of run a divided 6 ft shelf actually offers.
Start with the run, not the shelf. A 1.83 m (6 ft) shelf with a 25 mm centre divider leaves about 1.80 m of usable run; every fit count on this page is reckoned against that 1.80 m, not against the nominal 6 ft.
Then divide by the spine. A 250–450 page paperback block stands 15–28 mm thick, which is why the trade count lands in a band rather than a single number: 1,800 mm of run at 15–28 mm a copy gives 60–95 books. Mass-market stock, slimmer again, reaches 95–140.
Format swings the count harder than any other choice. Between the thickest hardcover spines (25–40 mm) and the slimmest mass-market, a shelf's book count varies roughly threefold — the full workings sit in the format table at /book-format-sizes.
Measure upright to upright and subtract 25 mm for each divider. A nominal 1.83 m shelf works out at 1.80 m of usable run.
Trade paperbacks at 15–28 mm give 60–95 per run; mass-market gives 95–140; hardcovers at 25–40 mm give roughly 45–72.
Opening quantity for a new title: 1.5–2× the copies sold in the same period of the previous year. Reorder at 2–3 weeks of average sales.
978 or 979 prefix, up to 5 registrant digits, item code, mod-10 check digit. ISBN-10 converts by prefixing 978: 0306406152 becomes 9780306406157.
First printings of adult trade fiction run 3,000–15,000 copies; reprints run 10,000–50,000. The band follows the printing, not the title.
Out-of-print at 3–10× cover; in-print remainders at 40–60% off; current hardcovers at 30–50% off. A jacketless hardcover loses the jacket's 10–20%.
A shelf's book count varies roughly threefold between formats — measure the run before you promise it a home.
Order 1.5–2 times last year's same-period sales; reorder when 2–3 weeks of stock remain.
| Format or display | Size | Page count | Run taken per copy | What fits |
|---|---|---|---|---|
| Trade paperback | 135 × 216 mm (5.25 × 8.5 in) | 250–450 | 15–28 mm spine | 60–95 copies per 1.80 m |
| Mass-market paperback | 110 × 178 mm (4.25 × 7 in) | 175–300 | about 13–19 mm spine (from the fit count) | 95–140 copies per 1.80 m |
| Hardcover, 6 × 9 in | 152 × 229 mm | 300–700 | 25–40 mm spine | about 45–72 copies per 1.80 m (derived) |
| Spine-out display | one spine width per title | any | the spine band above | about 30 titles per metre |
| Face-out display | one cover width per title | any | the cover width | about 10 titles per metre |
| Face-out, 30 cm title | 300 mm face | any | 0.30 m of run | 6 copies per 1.80 m |
| Face-out, 13 cm slimline | 130 mm face | any | 0.13 m of run | about 13 copies per 1.80 m |
The figures on this page restate the trade's working conventions for formats, print runs and second-hand price bands rather than any single publication, because these are the numbers the trade itself works to.