IKEA BILLY bookcase dimensions (80 and 40 wide, 202 and 106 tall) and shelf sizes — dimension sheet
Source: Xem Studio, https://xemstudio.com/objects/ikea-billy/  (CC BY 4.0)
Basis: IKEA product pages (measurements section)
Catalog version: 2026-10-20

Sizes: see table below
- All BILLY are 280 mm deep. Shelves are 20 mm thick, 260 deep: 760 long for the 80 cm case, 360 for the 40 cm case.
- Shelves sold now do not fit bookcases bought in spring 2014 or earlier (IKEA's note).
- Shelf-pin holes: owners report 5 mm holes on a 32 mm vertical pitch (the common 32 mm system); IKEA does not publish them. The 5 mm pins on this site fit them.
- Load per shelf: 30 kg (80 wide), 14 kg (40 wide).

part  width_mm  depth_mm  height_mm
BILLY 80 × 28 × 202  800  280  2020
BILLY 40 × 28 × 202  400  280  2020
BILLY 80 × 28 × 106  800  280  1060
BILLY 40 × 28 × 106  400  280  1060
shelf for 80 wide (20 thick)  760  260  20
shelf for 40 wide (20 thick)  360  260  20

Files elsewhere (not hosted by Xem Studio; license as stated by the publisher):
- IKEA (official product page): BILLY 80x28x202 — web — Manufacturer product page; dimensions are facts — https://www.ikea.com/mx/en/p/billy-bookcase-white-20522046/
- IKEA (official product page): BILLY 40x28x202 — web — Manufacturer product page; dimensions are facts — https://www.ikea.com/ae/en/p/billy-bookcase-white-50522040/
- IKEA (official product page): BILLY 80x28x106 — web — Manufacturer product page; dimensions are facts — https://www.ikea.com/my/en/p/billy-bookcase-white-70522044/
- IKEA (official product page): BILLY 40x28x106 — web — Manufacturer product page; dimensions are facts — https://www.ikea.com/in/en/p/billy-bookcase-white-90522038/
- IKEA (official product page): BILLY shelf 76x26 — web — Manufacturer product page; dimensions are facts — https://www.ikea.com/mx/en/p/billy-shelf-white-10525272/
- IKEA (official product page): BILLY shelf 36x26 — web — Manufacturer product page; dimensions are facts — https://www.ikea.com/my/en/p/billy-shelf-white-50525270/
- Hausbau-Forum (owner report): BILLY shelf pins: 5 mm holes, 32 mm pitch — web — Publisher's page; dimensions are facts — https://www.hausbau-forum.de/en/threads/billy-ikea-shelf-board-pencils-for-shelf-boards-wanted.23480

Xem Studio scan: not planned; the official CAD above covers it.
API: https://xemstudio.com/api/geometry?object=ikea-billy