Our sofa is from Crate & Barrel. We got it secondhand from a relative who had it for close to 10 years, and we have had it for three more.

It is still really comfortable to sit on. You sink in it, and I really like that feeling, especially after a long day.

That comfort is what you will live with every day. First, though, a sofa has to fit your room and make it through your front door, so grab a tape measure before you fall for one.

• How long should your couch be?
• Standard couch sizes
• How much room do I leave around it?
• Will it get through the door?
• Do you like to sink in or sit up?
• How tall is a couch, and how high is the seat?
• Which couch for a small living room?
• Questions people ask

How long should your couch be?

Start with the wall it will sit against. A sofa about two-thirds as long as that wall looks right, and it leaves room at each end for a lamp or a plant.

Then think about who sits there most nights. If it is usually just the two of you, a 72-inch sofa seats two adults comfortably.

And check the arms. Chunky ones take inches away from the seat, so on a short wall, slim arms give you more room to sit.

For an L-shaped sectional, measure both walls before you look at a single listing.

Standard couch sizes

How much room do I leave around it?

Leave 16 to 18 inches between the sofa and the coffee table. You can still reach your coffee from the seat, and nobody has to squeeze past your knees on the way to the kitchen.

Keep a clear path of at least 36 inches around a sectional, and a little more beside a chaise. A sleeper takes up a lot more space once the bed is out, so measure it open.

Try not to fill every inch, either. The way you use a living room changes over the years.

Ours has a West Elm Kista rug, medium pile, that we really like. These days it has a mattress topper on it and a playpen around it, because our 8-month-old crawls everywhere.

Will it get through the door?

Measure the whole way in before you order. Every doorway, hallway and stairwell between your front door and the living room counts, and so does every tight turn.

On the listing, look for the sofa’s diagonal depth next to its height and width. It is the sofa’s depth measured on a slant, the way it sits when it gets tilted back to go through a door.

That number has to be smaller than the width of each doorway on the way in, with room to turn it at every hallway corner.

If it is close, take off the cushions and the legs to make it smaller to carry in. Or look at a modular sofa, which comes in piece by piece.

Castlery’s Jonathan arrives fully built, in one piece, so check it against every doorway first. It is ready to sit on the day it comes.

Do you like to sink in or sit up?

If your sofa is where you nap and watch movies with your feet up, go soft, with a deep seat you can lean back in. If you sit up to talk, eat or work on a laptop, go firmer, with a shallower seat that holds you upright. A sofa more than 40 inches deep overall is made for leaning back and lying down.

Your height matters as well. The taller you are, the deeper the seat you need, so check the seat depth on the listing against your height.

Your height tells you how deep to go. How soft is up to you. Me, I like to sink in, as you can tell from our sofa.

If you are still torn between firm and soft, read the Castlery vs West Elm comparison. Castlery’s Jonathan is the firm one there, and West Elm’s two sofas are the kind you sink into.

If you can, sit on a few before you order, because firm and soft mean different things to different people.

How tall is a couch, and how high is the seat?

Most sofas stand 32 to 36 inches tall, from the floor to the top of the back. Check the seat height more carefully, because it decides how easily you get up.

A seat that is too low makes standing up awkward, and you feel it most on the sofa you use every day. Think about who will be getting up from it, an older parent, or you holding the baby.

If anyone in your house finds low seats hard, look at Castlery’s Owen. Its seat is 18.9 inches off the floor, about dining-chair height. The firm Jonathan sits lower.

Which couch for a small living room?

In a room of at least 10 by 12 feet, a 72-inch sofa is a good place to start. If you want three seats in a small apartment and you like to sit up, look at the Wade Logan Azriah. It is firm, with a shallow seat that keeps you upright with a laptop or friends over.

For one more seat when people come over, try an ottoman with a back. Our Ottomans With a Back roundup covers the ones with a fixed back and the ones that unfold into a bed.

Every living room page

• Best Ottoman With a Back
• Castlery Reviews
• Castlery vs West Elm
• Wade Logan Azriah Sofa Review

Questions people ask

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