What Is The Length Of a King Mattress? Size Guide & FAQs

If you’re wondering “What Is The Length Of a King Mattress”, you’re likely trying to figure out whether it will fit your bedroom, your height, or your existing bed frame. This guide explains the exact length of a standard king mattress, how it compares to other sizes, and what else to keep in mind before choosing one.

What Is the Standard Length of a King Mattress?

In most cases, a standard king mattress measures 80 inches in length (about 203 cm).

In the U.S. and many other regions, the common “Eastern king” or simply “king” is:

• Width: 76 inches
• Length: 80 inches

So when people ask “What Is The Length Of a King Mattress”, they are almost always referring to 80 inches long for the standard version.

Why Does the Length of a King Mattress Matter?

The length of your mattress affects:

• Comfort for taller sleepers – Taller individuals may feel cramped on shorter beds.
• Bedroom layout – An 80-inch-long mattress can significantly affect walking space, furniture placement, and door clearance.
• Fitted sheets and bedding – Bedding is sized to match common mattress dimensions; knowing the length ensures a proper fit.

A clear sense of how long a king mattress is helps avoid issues like bumping into the bed frame, difficulty opening closet doors, or overhanging bedding.

Are All King Mattresses the Same Length?

Not always. While the standard king is 80 inches long, there are a few variations:

Standard King vs. Other King Variants

Here is a simple comparison of common king-related sizes:

• Standard King: Wider than a queen, same length as a queen (80 inches), ideal for couples who want extra elbow room.
• California King: Slightly narrower but longer at 84 inches, often preferred by taller sleepers.
• Split King: Two twin XL mattresses placed side by side. Each is 80 inches long, so the total length is still 80 inches.

So, if your main concern is length, a California king at 84 inches offers more legroom than a standard king.

How Do I Know if an 80-Inch King Mattress Will Fit My Room?

Before choosing a king, consider:

• Room size: An 80-inch (6 feet 8 inches) mattress plus headboard and footboard can take up a large portion of the room.
• Walking space: Many people prefer at least a couple of feet of clearance around the bed for comfortable movement.
• Doorways and hallways: An 80-inch mattress can be bulky to maneuver; flexible or bending designs may help in tight spaces.

Measuring the room from wall to wall and sketching the placement of the bed can prevent surprises on delivery day.

FAQ: Common Questions About King Mattress Length

Is a King Mattress Longer Than a Queen?

No. A standard king and a queen are both 80 inches long.
The main difference is width:

• Queen: 60" × 80"
• King: 76" × 80"

If you want more length than a queen, a California king (72" × 84") is usually the next step up.

Is a King Mattress Long Enough for Tall Sleepers?

For many people, 80 inches is sufficient, but taller individuals may prefer extra length. A simple way to think about it: your height plus some room for pillows and stretching. Those who are particularly tall sometimes choose a California king for the added 84-inch length.

Do King Bed Frames and Headboards Match the Mattress Length Exactly?

Most king bed frames are designed for an 80-inch mattress, but the total footprint can be longer due to:

• Thick headboards
• Footboards
• Decorative frames or sleigh designs

This means the overall bed may measure more than 80 inches from end to end, even though the mattress itself is 80 inches.

What Should I Consider Besides “What Is The Length Of a King Mattress”?

When evaluating a king mattress, it helps to think about:

• Room layout: Windows, radiators, and doors can influence where the bed can go.
• Partner space: A king offers more width than length versus smaller sizes.
• Accessories: Sheets, protectors, and toppers all need to be sized to an 80-inch-long king.
• Future flexibility: If you might move to a smaller room, a king’s length and width may limit placement options.

✅ Quick Mattress Takeaways

Key points consumers should understand about What Is The Length Of a King Mattress:

• A standard king mattress is 80 inches long.
• It typically measures 76" wide × 80" long.
• Standard king and queen mattresses share the same 80-inch length; the king is just wider.
• A California king is longer at 84 inches, but slightly narrower.
• Bed frames and headboards can make the total bed longer than the mattress itself.
• Measuring your room and considering walking space helps ensure an 80-inch king mattress fits comfortably.

Understanding What Is The Length Of a King Mattress—and how it compares to other sizes—makes it easier to choose a mattress that fits both your body and your bedroom, supporting a more comfortable and practical sleep space.