Twin Size Bed Dimensions:
A Size Breakdown

UPDATED

Written by David Rubin

Expert Tested

Table of Contents

The twin size bed is popular worldwide thanks to its affordability and versatility. Twin mattresses are widely available and you can find them in a range of construction and material types. Twins comfortably fit one person and take up very little floor space, so they’re excellent for small apartments, RVs, and other areas with limited room.  

Twin mattresses are best for people who sleep alone because they’re narrower than full, queen, and king size mattresses. While standard twins may be too short for some sleepers, twin XL mattresses are long enough to accommodate taller adults.

If you want to find the best twin mattress of 2024, take a look at our top picks. Our choices for the best mattress also include great options for twin beds.

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Dimensions of a Twin Size Bed

A twin size mattress measures 38 inches wide by 75 inches long. It is the smallest of the six standard mattress sizes. Twin XL mattresses have the same width but measure 80 inches long. Full, queen, king, and California king are all significantly wider than twin beds, though full size mattresses have about the same length. 

Because twin size mattresses are one of the most popular bed dimensions, it’s easy to find bedding, sheets, and other sleep accessories that fit.

What Is the Difference Between a Twin and Twin XL?

Twin XL mattresses are five inches longer than standard twins are, making them a better fit for taller people. Both dimensions share the same width and each option is easy to find and purchase. You should expect to pay more for twin XL mattresses and bedding because it takes more materials to manufacture them.

When choosing between twin vs. twin XL, length and bedroom space are the most critical factors. It’s also important to look closely at your intended bed base or frame, as the mattresses are not interchangeable with each other.

Mattress SizeDimensions
Twin38″ x 75″
Twin XL38″ x 80″

Who Should Consider a Twin Size Bed?

It’s important to consider mattress size while you shop and think about what will best fit your bedroom. Twin size mattresses are an excellent option for children as well as many teens and adults. They’re also a worthy choice for anyone seeking an affordable bed.

Twin mattresses are the most economical choice for a single bed and there are options for nearly any budget. They can fit almost anywhere, including notoriously tough spaces like bunk bed frames, boats, RVs, and dorm rooms. 

However, because of their small size, twin beds aren’t the right choice for everyone. People 6 feet or taller may prefer a twin XL instead. Twins also aren’t a good choice for people who share the bed because they’re too narrow for two people to sleep on comfortably.

About The Author

David Rubin

Certified Sleep Science Coach, Director of Product Testing


David is a Certified Sleep Science Coach with a lifelong passion for well-being and health optimization. His interest in sleep developed with the arrival of his son, when sleep suddenly became a precious commodity.

  • POSITION: Side Sleeper
  • TEMPERATURE: Hot Sleeper
  • CHRONOTYPE: Lion

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