Mattress Sizes & Dimensions: Twin Through California King

Standard U.S. Mattress Size Chart

What Size Mattress Is 60 × 80?

A 60 × 80-inch mattress is the standard nominal size of a Queen mattress in the U.S. If an existing mattress measures around 59–60 inches wide and roughly 79–80 inches long, it is most likely a Queen. Small finished-size variations are normal.

What Size Mattress Is 76 × 80?

A 76 × 80-inch mattress is the standard nominal size of a King. A King gives couples more width than a Queen while keeping the same nominal 80-inch length.

What Size Mattress Is 72 × 84?

A 72 × 84-inch mattress is a California King. California King is four inches narrower and four inches longer than a standard King, so it favors extra length over maximum width.

What Size Mattress Is 38 × 80?

A 38 × 80-inch mattress is a Twin XL. Twin XL has approximately the same width as a Twin but adds about five inches of length. Two Twin XL mattresses placed side by side form the typical split-king footprint.

Queen vs. King: Which Size Should You Choose?

Do not choose from mattress dimensions alone. Measure the full bed frame, nightstands, door swing, dresser drawers and walking path. Frames can be wider and longer than the mattress itself.

King vs. California King

What Is a Split King Mattress?

A split King usually uses two Twin XL mattresses side by side. Each Twin XL is approximately 38 × 80 inches, creating an overall footprint close to a standard King. This configuration is common with dual adjustable bases because each side can move independently.

If two sleepers want different mattress feels, a split King can also allow different Twin XL comfort choices, but the two mattresses should have compatible heights and the entire setup should be checked for base and frame compatibility.

Mattress Height vs. Mattress Size

Width and length determine the nominal mattress size; height is a separate measurement. Mattress height matters for fitted-sheet pocket depth, total bed height, headboard appearance and adjustable-base setup. A Queen can be 10 inches tall or 16+ inches tall and still be a Queen.

For more help planning the finished height, see the bed-height guide.

How to Measure Before Buying a Mattress

1. Measure the usable floor area where the full bed frame will sit.
2. Measure doors, hallways, stair turns and elevator openings on the delivery path.
3. Check the inside dimensions of an existing frame or platform.
4. Confirm the foundation or adjustable base uses the same nominal size as the mattress.
5. Check mattress height before buying fitted sheets or protectors.
6. Verify the exact finished dimensions on the product page when frame clearance is tight.

What If Your Mattress Measures 52 × 72, 54 × 80 or Another Nonstandard Size?

Those measurements do not match the six most common standard U.S. mattress sizes exactly. They may indicate a specialty mattress, RV mattress, antique frame, custom mattress or simply a measuring difference. Measure width and length at the widest points and check the bed or manufacturer label before ordering a replacement.

For example, a standard Full is nominally about 54 × 75 inches; a standard Queen is about 60 × 80. A mattress around 54 × 80 is therefore longer than a typical Full but narrower than a Queen and should not automatically be treated as either size.

Compare popular mattresses by available size

Most popular models are offered in several standard sizes, but exact choices vary by product and configuration. Confirm the live product options before ordering.

Mattress Size FAQs

Are all Queen mattresses exactly 60 × 80 inches?

No. 60 × 80 inches is the common nominal U.S. Queen size, but finished measurements can vary slightly by manufacturer and construction.

Is a King the same length as a Queen?

Yes, nominally both are about 80 inches long. A King is wider: approximately 76 inches versus about 60 inches for a Queen.

Is California King bigger than King?

It is longer but narrower. California King is about 72 × 84 inches, while standard King is about 76 × 80 inches. Neither is simply larger in every direction.

Is Twin XL half of a King?

Two Twin XL mattresses together create the typical split-king footprint. Because finished dimensions can vary slightly, confirm the specific mattresses and base before ordering.

Can I use a Queen mattress on a Full frame?

No. A Queen is substantially wider and longer than a standard Full, so the frame and mattress dimensions do not match.

Do adjustable bases use the same mattress sizes?

They generally use standard nominal sizes, but split configurations are common. Confirm that the mattress and base are compatible and match the exact size configuration before purchase.

How much space should I leave around a bed?

There is no single room-layout rule that works for every bedroom. Measure walking paths, furniture, doors and drawers and choose a size that leaves the room functional for your needs.

Reviewed September 1, 2026 by Lawrence “Larry” Heilers, Texan Mattress owner and mattress specialist since 2000.