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What Size Is a King Bed Frame? Do You Know the Exact Measurements?

Mirror in the bedrooM

King beds are very large and desirable. King mattresses can easily accommodate two adults and a pet or a mother and her kids. The large size makes king beds spacious, but it can also make it difficult to fit them into a space. A king size mattress measures 76 inches wide and 80 inches long and is the largest mattress available. However, to accommodate the size of the mattress, bed frames need to be even larger than the mattress itself. So, how large do king bed frames typically run?

A king bed frame will be roughly two inches wider and two inches longer than a king mattress. That makes the average king-size frame 78 inches wide by 82 inches long. But these frames can be smaller or larger than this, depending on the style. Knowing the exact size of your bed frame can be critical to properly filling out a bedroom space.

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Small Frames

Some bed frames are very minimal and very snug. The smallest frames might only be half an inch to an inch wider and longer than the mattress. That puts the dimensions for the smallest bed frames at just 77 inches wide and 81 inches long. These frames are going to be minimalistic, modern, and simple, but they will be the best option for someone trying to fit a king bed into a smaller space.

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Average Frames

The average bed frame typically adds two to four inches per side in order to accommodate the mattress. That makes the average king bed frames 78 to 80 inches wide by 82 to 84 inches long. These frames are the most common and can range from very simple to a little more elaborate. Average sized king bed frames are large enough to fit a headboard as well. A headboard will add another inch to the length of the bed and is generally two to four inches wider than the mattress.

Adding a headboard will make the average bed frame measure 80 inches wide by 85 inches long.

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Large Frames

Large frames are less common than average or small frames, but they are still available for those who want them. Large king frames are usually more elaborate than standard bed frames. Large frames might include bed posts, built-in headboards, sleigh ends, or large footboards. Large king frames are generally five inches wider and longer than the mattress itself. The dimensions of large king frames are typically 81 inches wide by 85 inches long. That is a considerable size that can easily crowd the average bedroom.

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Measure Twice, Buy Once

If you are set on buying a king mattress, you will also need a king bed frame. Bed frames can vary in dimensions by half a foot on the extreme ends. Six inches might not sound like a lot, but when you are trying to furnish and arrange a bedroom, it can make all the difference. Before buying a bed frame, you should measure the space where you want to put your bed and account for the extra space a bed frame will occupy. You should measure for the larger bed frame sizes just to see what the room might look like with a larger frame. Make sure that your mattress and frame will fit your bedroom. A common mistake is for people to measure the size of the mattress alone without accounting for the frame itself.

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Width (Inches) Length (Inches)
Small Frame 76.5 – 78 80.5 – 82
Average Frame 78 – 80 82-84
Large Frame 80.5 – 82+ 84.5-86+

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King bed frames can range from just 76.5 inches wide all the way to 82 inches wide or more. Similarly, the length can range from 80.5 to 85 inches or more. That is a fairly widespread in size, so be sure to measure before you make any final decisions. Failing to account for the extra length and width of a bed frame can throw off your plans and spacing in your bedroom redesign.

The more elaborate or complex the bed frame, the larger the dimensions. Things like headboards, footboards, and wide runners can add a lot of extra dimension. Smaller frames are usually more streamlined, minimal, and modern and therefore do not add as much in the way of bulk to your bed. Choose the style and size that is ultimately right for you.

Featured Image Credit: Pixel-Shot, Shutterstock


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