Here’s a mistake I’ve made—and you’ll probably make it too, because we’re all human and we like big things. You see a beautiful, 18-inch-deep bookcase on sale. It looks majestic. You buy it.
Then you put your books on it, and suddenly you can’t see half of them because they’re buried in the shadows. You now own a bookcase that functions as a cave system. You’ll have to stack books in two rows just to fill the space, which means the back row becomes a secret museum of forgotten volumes.
That’s fine if you’re running a library for hobbits, but for most of us, anything over 13 or 14 inches is overkill. Your books will thank you for not forcing them to live in a dark, dusty grotto.
Measuring Like a Pro (Without Crying)
So how do you know what depth is actually right for you? Grab a book you love—the biggest, chunkiest one you own. Place it on a table. Now, measure from the table edge to the back of the book, and add 2 inches for aesthetic breathing room.
Depth Of Standard Bookshelf at Hamish Shah blog
That number? That’s your ideal depth. Congratulations, you’ve just become a certified bookcase anthropologist. (The certification isn’t real, but I’m proud of you anyway.)
And remember: the average depth is a guideline, not a rule. If you want a bookcase that’s 10 inches deep because you’re only storing poetry chapbooks—go for it. If you want a 16-inch behemoth for your vinyl and your cat to nap on—power to you.
