The size of the ottoman you buy will depend on what you intend to use it for. If you want an ottoman or two for occasions when you might need extra seating, a smaller size is the way to go.
A small ottoman can be tucked away in a corner, under a console table or stored in a closet. Ottomans that are small to medium size can also be used as a footrest or extra surface. If you like your furniture to be versatile, or if you like to change up your room often, a small ottoman is best.
If you want a coffee table alternative, select a large ottoman. Size your coffee table ottoman the same way you would a regular coffee table, typically about two-thirds the length of your couch.
A big ottoman is also a great option if you want living room seating that’s different from your couches and chairs to mix up the space. An oversized ottoman can potentially seat more than one person but is still smaller than a traditional loveseat, making it an excellent option for tight spaces.
For ottomans that will accompany seating, just make sure the height is about one inch lower than the seat cushions.