The best way is to measure the height (spine) of your book and compare this against our size chart, which you'll find in the product images for each listing.
In general, we recommend:
- Tall hardcovers: Large (L) size
- Tall paperbacks: Medium (M) size
- Short hardcovers & regular US paperbacks: Small (S) size
- Short paperbacks: Extra-small (XS) size
- Need a more snug size for US paperbacks, but XS is too small? Go for Demi-small (DS) size
For more info, check out our blog post here