Choosing what size mattress you need seems like a no brainer, but there are several factors to keep in mind beyond just different mattress sizes.

Your current sleeping arrangement and living space could be the reason you buy a twin XL instead of a full, while future plans may lead you to purchase a king over a queen.

When it comes to mattresses—one size does not fit all, but we’re here to share all the information you need to make the right decision. Let’s walk through the sizes together–consider this your mattress size guide!

Before we jump into the benefits of sizes, here's a quick mattress size chart for reference: Twin | 39x75 inches Twin XL | 39x80 inches Full | 54x75 inches Queen | 60x80 inches King | 76x80 inches California King | 72x84 inches.

Twin (39 x 75): The twin offers just the right amount of space for solo sleepers of any age. It’s compatible with special frames like daybeds and bunk beds, and won’t crowd even the smallest of rooms. Because of its narrow width, the twin isn’t perfect for arm stretchers or rollers, but stationary sleepers looking for something minimal and cost effective—meet your match!

Twin XL (39 x 80): The twin XL boasts an extra 5” in length, offering more leg room for people who are tall or on the verge of a growth spurt. We recommend the XL for snoozers—young or old—who are 5’8’’ to 6’3’’. Even shorties may want the extra length, especially if they have pets that like sleeping at the foot of the bed. The XL is often used for dorm rooms and split king setups, but it will fit in a variety of spaces. Just keep in mind that finding frames and accessories can be tricky because the XL isn’t as popular as the twin or full.

Split King (2 twin XLs): Two twin XLs walk into a bedroom...and become a split king. Yup, the split king is two twin XLs put together. This setup works well for shared beds with people who have different sleep schedules or comfort preferences. It’s also compatible with adjustable frames (with sides that move independently). These can be broken down into single parts, which simplifies moving and set up, but bear in mind that not all frames and accessories are compatible with split kings.

Full (54 x 75): The full, sometimes called double, works well in many situations. It’s small enough to fit into compact spaces, but offers just enough space for pairs. This size is a practical choice for guest rooms, as well as **co-sleeping, urbanites, parties of one, couples that don’t need a lot of space to move, growing kids, and pet parents who always save a spot for their fur babies. If you like to accessorize your bed, take into account that not every brand or style is available in this size.

**We recommend consulting with a professional before co-sleeping with an infant or young child.

Queen (60 x 80): The queen delivers more space without the overwhelming footprint of a king. It accommodates couples, co-sleepers, growing families (with kids and pets), and even lone wolves who want to roam free. Fulls and queens are a smart choice for city dwellers who want a bed that’s big enough to stretch out on, but doesn’t crowd their tiny homes. Queens and kings are among the highest selling sizes so there are plenty of sheets, frames, and accessories available at varying price points.

King (76 x 80): The king works well in big rooms and is a top pick for couples and families with extra space. The size allows sleepers to spread out—a must when sharing a bed with a restless or hot sleeper who tosses and turns, or someone who runs on a different sleep schedule. People who have (or want) human kids or pet kids will need the 76” width—it’s a luxury when the kids start enjoying your bed more than their own, trust us.

California King (72 x 84): **Contrary to popular belief, the Cal king is not bigger than a regular king. It’s the slimmer version of the king that fits more easily into small or awkward spaces (although it may be more costly and time-consuming finding accessories in this size). With the loss of 4” in width, Cal king users gain 4” in length. The width is still accommodating for singles or couples who want a little rolling room, but the extended length is the highlight. Tall people (6’0’’ and up) who need to stretch out and pets who like lying at the foot of the bed will appreciate the longer length.

**King and Cal king mattresses have different dimensions. To avoid order mixups, check the size of your existing frame (or accessories) before making a purchase. Remember: California kings, like the state, are long and narrow.

A mattress is an investment you don’t want to replace or exchange every couple years—we understand. There is no right or wrong answer to “What size mattress is best for you?” Take time to think through your current situation and where the future might lead, and you’ll find your fit!