Bookcase Capacity Calculator
Running out of shelf space mid-collection means stacking books sideways or double-rowing them, both of which make things harder to find. Enter roughly how many books you have below to see how many shelves — and bookcases — you need.
Work out how much bookshelf space you need
Enter roughly how many books you have and your shelf length.
For 150 books, you'll need approximately:
6 shelves
That's around 2 standard bookcases (assuming 5 shelves each).
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Pros
- Gloss doors on a matt white frame
- Push-to-open handleless doors
- Standard 180cm height suits most bedrooms
Cons
- MDF-based construction typical for this price point
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Pros
- Black metal frame with wood-effect shelves
- Mix of open shelving and enclosed storage
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Cons
- Fewer shelves than a classic 5-tier bookcase
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Pros
- Solid oak — not veneer
- Adjustable internal shelf
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Cons
- Smaller footprint than some premium sideboards
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Frequently asked questions
How much shelf space does the average book take up?
A typical paperback takes up around 2-2.5cm of shelf width when stood upright, while hardbacks are usually 3.5-4.5cm depending on the edition. A mixed collection averages out to roughly 3cm per book.
Should I organise books by size or by subject?
Organising by subject or author is more practical for finding books, though grouping similar heights together on the same shelf makes better use of vertical space and looks tidier than a mix of tall and short spines.
Is deeper shelving always better for books?
Standard paperback and hardback depths (around 20-25cm) suit most collections, but oversized books like coffee table books, art books or graphic novels may need deeper shelving to avoid overhanging the edge.
How much weight can a typical bookcase shelf hold?
It varies by material and design, but many mid-range bookcase shelves are rated for 15-25kg each — worth checking if you have a particularly dense collection of hardbacks, since books are surprisingly heavy in bulk.