By Team Quiltdom
Use this free quilt size calculator to find out how many blocks you need for a quilt that fits your bed. Pick a mattress size, choose how far you want the quilt to hang over the sides, enter your block size, and it tells you how many blocks to make, how to lay them out, and the finished size of your quilt.
It works for any bed, from a baby quilt to a California king, and for any square block size.
Quilt Size and Block Calculator
All measurements in inchesNext step: work out the backing and batting for this quilt.
The calculator rounds up to whole blocks, so your quilt will be the same size as the area you need to cover or a little bigger. The drop is added to both sides and the foot of the bed, and to the top too if you add a pillow tuck. Borders are added outside the blocks.
How To Use The Quilt Size Calculator
- Pick your mattress size. Tap a mattress button, or type the width and length of your mattress. Measure the mattress itself if you can, since pillow-top and deep mattresses vary.
- Set the drop. The drop is how far the quilt hangs over the sides and foot of the bed. Each mattress button fills in a typical drop, and you can change it. A coverlet that just covers the mattress is about 10 to 12 inches. A quilt that reaches the bed skirt is often 14 to 16 inches.
- Enter your finished block size. Use the size the block will be once it is sewn into the quilt, not the cut size. A 12 inch finished block is cut at 12 1/2 inches.
- Add a border if you plan one. Enter the border width for one side. The calculator puts it outside the blocks, so you need fewer blocks.
- Read your results. You get the number of blocks to make, how many go across and down, the finished size, and the size with one row and one column fewer, in case you would rather make a slightly smaller quilt.
When your quilt size is set, use our quilt backing calculator to find out how much backing fabric and what size batting to buy.
How To Calculate How Many Quilt Blocks You Need
Here is the math the calculator does, using a queen mattress (60 x 80 inches), a 14 inch drop and 12 inch finished blocks.
- Add the drop to the width. The quilt hangs down both sides, so add the drop twice: 60 + 14 + 14 = 88 inches.
- Add the drop to the length. The quilt hangs over the foot of the bed but not the top, so add the drop once: 80 + 14 = 94 inches. For a pillow tuck, add it twice.
- Divide by your block size and round up. 88 ÷ 12 = 7.3, so you need 8 blocks across. 94 ÷ 12 = 7.8, so you need 8 blocks down.
- Multiply. 8 x 8 = 64 blocks, for a finished quilt of 96 x 96 inches.
The formula: blocks across = (mattress width + 2 x drop) ÷ block size, rounded up. Blocks down = (mattress length + drop) ÷ block size, rounded up. If you add a border, subtract twice the border width before you divide.
Quilt Size Chart: Blocks Needed For Each Bed Size
This chart uses 12 inch finished blocks, no border, no pillow tuck and the typical drop for each bed. Change any of these in the calculator above to fit your quilt.
| Bed | Mattress | Drop | Size to cover | 12 in blocks | Finished quilt |
|---|---|---|---|---|---|
| Baby quilt | 32 x 42 in (finished size) | 0 in | 32 x 42 in | 3 x 4 = 12 | 36 x 48 in |
| Crib | 28 x 52 in | 2 in | 32 x 54 in | 3 x 5 = 15 | 36 x 60 in |
| Twin | 38 x 75 in | 12 in | 62 x 87 in | 6 x 8 = 48 | 72 x 96 in |
| Twin XL | 38 x 80 in | 12 in | 62 x 92 in | 6 x 8 = 48 | 72 x 96 in |
| Full | 54 x 75 in | 14 in | 82 x 89 in | 7 x 8 = 56 | 84 x 96 in |
| Queen | 60 x 80 in | 14 in | 88 x 94 in | 8 x 8 = 64 | 96 x 96 in |
| King | 76 x 80 in | 14 in | 104 x 94 in | 9 x 8 = 72 | 108 x 96 in |
| California king | 72 x 84 in | 14 in | 100 x 98 in | 9 x 9 = 81 | 108 x 108 in |
For more standard sizes, see our guide to quilt sizes.
Baby And Crib Quilt Sizes
Crib quilts: Safety comes first. To keep extra fabric away from a baby's face, a crib quilt should generally be no longer than the mattress, with only a modest overhang of 4 to 5 inches in total so it can tuck in lightly. A common finished size is about 32 x 52 inches.
Baby quilts: These are smaller than crib quilts and work well for swaddling or tummy time. A common finished size is 32 x 42 inches, large enough to wrap an infant but small enough that one yard of backing and batting will cover it.
Quilt Size Calculator FAQ
How many 12 inch blocks do I need for a queen size quilt?
For a queen mattress (60 x 80 inches) with a 14 inch drop on the sides and foot, you need 64 blocks, laid out 8 across and 8 down. That makes a 96 x 96 inch quilt.
How many blocks do I need for a twin quilt?
With 12 inch blocks and a 12 inch drop, a twin quilt takes 48 blocks, 6 across and 8 down, for a finished size of 72 x 96 inches.
What size should I cut my quilt blocks?
Cut each block 1/2 inch larger than its finished size to allow for a 1/4 inch seam on every side. A 12 inch finished block is cut at 12 1/2 x 12 1/2 inches.
How much should a quilt hang over the side of the bed?
Most quilts hang 10 to 16 inches over the sides. Around 12 inches covers the mattress like a coverlet. Around 14 to 16 inches reaches the bed skirt on a standard bed. Measure from the top of your mattress to where you want the quilt to stop.
Does the drop go on all four sides?
No. The drop goes on both sides and the foot of the bed. The top edge usually sits at the pillows, unless you want a pillow tuck, which adds the drop at the top as well.