How To Make A Bed Quilt The Right Size

There are many very mundane things you must take into account when deciding what size to make a bed quilt. Here’s a step-by-step run-down of everything you need to know exactly how big to make quilted comforters and bedspreads.

Sizing Your Quilt Top

Start with the size of the bed’s mattress. Fortunately, mattress sizes are fairly standard:

Crib	23″ by 46″
Twin	39″ by 75″
Double	54″ by 75″
Queen	60″ by 80″
King	78″ by 80″
California King	72″ by 84″

Next, compute the “drop” — the amount of quilt you’ll need to hang over the edge of the mattress on each side and at the foot.

If you are making a quilted comforter, then you can find the drop by measuring the depth of the mattress, then adding 3″ to cover where the mattress meets the box spring. For example, a mattress depth of 10″ plus 3″ to cover where the mattress meets the box spring would give you a 13″ drop.

If you are making a quilted bedspread, then your drop is the measurement from the edge of the mattress to the floor. On my bed, that’s 25 inches.

Compute The Width

Now that you know the size of the mattress and how much drop you need, you’re ready to compute the width of your quilt.

Add your drop twice to the width of the mattress. (You’re adding the drop twice because the quilt needs to hang down both sides of the mattress.)

For example, if you are working on a quilted spread for a queen-size mattress, add 60″ (the mattress width) plus the drop on one side (let’s say 13″, for example), plus the drop on the other side (13″ again). This gives you a total quilt width of 86 inches.

Compute The Length

Finally, you need to compute the length. Start by adding the length of the mattress to the drop.

If you are going to put your pillows on top of the quilt and use pillow shams, you’re done. For example, a queen-size mattress (80″) with a 13″ drop would give you a total length of 93 inches.

However, if you want a pillow tuck, you have to add another 12″ to 16″ (depending on the height of your pillows and how deep a tuck you like) to the length. So for a queen-size mattress (80″) with a 25″ drop and a 14″ pillow tuck, the length of your quilt would be 119 inches.

If you are going to make a quilt for a gift and only know the nominal size of the recipient’s mattress (double, queen, king, etc.) then your best bet is to make it a comforter, not a spread. Since you can buy pre-cut comforter batts for the common mattress sizes (see below), simply make the quilt top 6″ smaller than the length and width of the batting sold for that size bed.

Sizing Your Batting

If you are having your quilt done on a long-arm machine, you will need extra batting and backing to wrap on the machine. Check with your long-arm machine quilter to find out how much extra she would like to work with.

When you check, be sure you’re clear whether the figure she gives you (let’s say 6″) refers to the total extra batting and backing you should buy (i.e. 3″ for the top edge and 3″ for the bottom edge), or to the amount of extra she needs on each edge (i.e. 6″ top and 6″ bottom, for a total of 12″ extra).

Or you can eliminate the issue altogether by simply buying your batting from the long-arm quilter. She will cut a piece of batting to fit your top when she puts it on her machine.

Quilting On A Frame

If you decide to do the quilting yourself on a frame, check the frame manufacturer’s instructions for how much extra batting to purchase.

If you are quilting in a hoop, you can get by with 2″ or 3″ of extra batting on each side and each end.

Buying Batting

Buying batting in the size you need it can be a little tricky. First, consider whether one of the common pre-cut batt sizes will work for you:

Crib	45″ by 60″
Twin	72″ by 90″
Double	81″ by 108″
Queen	90″ by 108″
King	120″ by 120″

Pre-cut crib-size and queen-size batts are easy to find and come in many types and materials. King and double are also fairly easy to find, although not in as many different types and materials as queen-size and crib-size. But twin-size batts are fairly uncommon in any type or material.

If your quilt shop doesn’t carry a batt in the size you want, you can buy the length you want cut from a large roll of batting.

If you buy your batt from a roll, be sure to check the width of the batting on the roll. Often the batting is folded in half and then wrapped on the roll, so it is really twice as wide as it appears. But this is not always true, so check the real width before you decide how much to cut.

Another reason to buy your batting from a roll would be to accommodate an unusual-size quilt. For example, many quilted spreads won’t work well with pre-cut batts, which are sized with comforters, not spreads, in mind.

Sizing Your Backing

I usually make my backing piece 1″ or 2″ bigger than my batting in all directions. That gives me some adjustment room for lining up the batting and the top with the backing.

When I’m done quilting, I trim the excess batting and backing and put the scraps of backing in the pile to use for scrap quilts.