Quilting guide
Fat quarter size: dimensions, cuts and how many you need
Updated by Khokhar Sab
A fat quarter is 18 × 22 inches: a half yard of fabric cut in half along the fold. Once the selvage is trimmed, plan on about 18 × 21 inches of usable fabric. Four fat quarters make one yard. Some UK shops sell a metric fat quarter of 50 × 55 cm, which is a little bigger.
Fat quarter size in inches and centimeters
Wikipedia describes the cut: take a half yard from the bolt, then cut it in half across its width. You get a piece the same area as a quarter yard, in a squarer shape. Quilting cotton comes off the bolt about 42 to 44 inches wide, so half of it is 21 to 22 inches.
- As cut: 18 × 22 inches, or 45.7 × 55.9 cm.
- Usable: about 18 × 21 inches (45.7 × 53.3 cm) once the selvage comes off. Treasurie's precut chart lists this size.
- Range: Designed to Quilt notes that real fat quarters run from 18 × 20 to 18 × 22 inches, because bolts vary from 40 to 44 inches wide.
The fabric yardage calculator plans on 18 × 21 inches, the usable size. Every number on this page uses that size too.
Fat quarter vs long quarter vs fat eighth
A long quarter is the plain quarter yard: 9 inches cut across the full width of the bolt. It holds the same fabric as a fat quarter. Designed to Quilt puts both at 378 square inches. A fat eighth is half a fat quarter.
| Cut | Inches | Centimeters | How it is cut |
|---|---|---|---|
| Fat quarter | 18 × 22 | 45.7 × 55.9 | Half yard, cut in half along the fold |
| Long quarter | 9 × 42 to 44 | 22.9 × 106.7 to 111.8 | Quarter yard across the full width |
| Fat eighth | 9 × 22 or 18 × 11 | 22.9 × 55.9 or 45.7 × 27.9 | A fat quarter cut in half either way |
| Metric fat quarter | About 20 × 22 | 50 × 55 | Half meter, cut in half along the fold |
| Metric long quarter | About 10 × 44 | 25 × 110 | Quarter meter across the full width |
Treasurie gives both fat eighth shapes. Pelenna Patchworks, a UK shop, lists the metric sizes. A 50 × 55 cm fat quarter holds about 8% more fabric than an 18 × 22 inch one, so check which kind a pattern means.
The shape changes what you can cut. A long quarter is only 9 inches tall, so it can't give a 10 inch square at all. A fat quarter gives 2. For strips longer than 22 inches, only the long quarter works.
How many fat quarters in a yard?
Four fat quarters make one yard, as Treasurie and Designed to Quilt both state. The math follows from the cut.
- 1 yard = 4 fat quarters = 8 fat eighths
- ½ yard = 2 fat quarters
- ¼ yard = 1 fat quarter or 1 long quarter
So when a pattern asks for 1½ yards of one print, 6 fat quarters hold the same area. They only work if no piece is longer than about 21 inches.
How many squares can you cut from a fat quarter?
This table comes from the calculator's own logic. It counts squares across the 21 inch side and down the 18 inch side. The sizes are cut sizes, with seam allowance included. The last column shows a 9 × 42 inch long quarter from the same bolt.
| Square size | From a fat quarter | Layout | Fabric used | From a long quarter |
|---|---|---|---|---|
| 2.5 in | 56 | 8 × 7 | 93% | 48 |
| 3 in | 42 | 7 × 6 | 100% | 42 |
| 3.5 in | 30 | 6 × 5 | 97% | 24 |
| 4 in | 20 | 5 × 4 | 85% | 20 |
| 5 in | 12 | 4 × 3 | 79% | 8 |
| 6 in | 9 | 3 × 3 | 86% | 7 |
| 10 in | 2 | 2 × 1 | 53% | 0 |
Three inch squares use every inch of the fat quarter. Ten inch squares, the layer cake size, leave 47% of it as scraps. Five inch charm squares give 12 per fat quarter but only 8 from a long quarter.
Sources disagree on small squares because they start from different widths. Treasurie counts 99 two inch squares, using the full 22 inches. Designed to Quilt counts 90, using 21 inches, and so does the calculator (90). If your fat quarter measures a full 22 inches after trimming, you gain one column.
For half-square triangles, cut squares a little larger than these. The half-square triangle methods guide gives the cut sizes for each method.
How many 2½ inch strips from a fat quarter?
A 2½ inch strip is the jelly roll and binding width. One fat quarter gives either:
- 7 strips 21 inches long, cut parallel to the long side, for 147 inches in all.
- 8 strips 18 inches long, cut parallel to the short side, for 144 inches in all.
The 147 inches equal about 3.5 jelly roll strips, which run 42 inches long in Treasurie's chart. A long quarter gives 3 strips 42 inches long, 126 inches in all. That is less length, but with fewer seams to join.
Fat quarter strips can make a scrappy binding. The binding calculator works out the total length your quilt needs.
Fat quarters or yardage for the same cut
The fabric yardage calculator counts fat quarters as well as yards. Here are four sets of squares run through it with its defaults: 42 inch fabric, 2 inches of selvage trimmed and 10% extra on the yardage.
| You need | Fat quarters | Same as | Yardage |
|---|---|---|---|
| 100 squares, 2.5 in | 2 | ½ yd | ⅝ yd |
| 40 squares, 5 in | 4 | 1 yd | ⅞ yd |
| 36 squares, 6 in | 4 | 1 yd | 1⅛ yd |
| 20 squares, 10 in | 10 | 2½ yd | 1⅝ yd |
The yardage column includes the 10% extra and the fat quarter column has none, so small squares come out close. Ten inch squares are the exception. They take 10 fat quarters, the same fabric as 2½ yards, against 1⅝ yards cut from the bolt.
How many fat quarters do you need for a quilt?
It depends on the pattern and on how much background fabric it uses. Yellow Umbrella Quilts gives these general ranges.
| Quilt size | Fat quarters |
|---|---|
| Baby | 16 to 20 |
| Twin | 24 to 30 |
| Queen | 36 to 45 |
| King | 48 to 56 |
The same site says its own patterns use fewer, from 3 to 6 for a baby quilt up to 24 to 30 for a king. It also notes that a fat quarter bundle usually holds 18 to 20 pieces. That makes a lap, twin or even queen quilt, depending on the background.
For a pattern, use its fabric list. For your own design, find the finished size on the quilt size chart and plan the top with the quilt calculator. Then enter your pieces in the fabric yardage calculator to get the fat quarter count.
Tips for buying fat quarters
- Plan on 18 × 21 inches. Designed to Quilt notes sizes vary with bolt width, so don't count on the full 22.
- Check the unit. A metric 50 × 55 cm fat quarter is bigger than a US one. Pattern counts written for one may not match the other.
- Match the cut to the pieces. Squares up to 6 inches use a fat quarter well. For 10 inch squares or strips longer than 21 inches, yardage or long quarters waste less.
- Buy one spare. The fat quarter counts above include no extra, so a spare covers a miscut.
- Mix print scale. Yellow Umbrella Quilts suggests combining solids, florals and geometrics, and thinking about color and scale.
- Wash with care. The same site suggests prewashing in gentle detergent and storing fat quarters folded or rolled to avoid creases.
Sources and further reading
Wikipedia's yard article defines the fat quarter and fat eighth. Treasurie's what is a fat quarter has a precut size chart in inches and centimeters. Designed to Quilt explains the size range and square counts in dimensions of a fat quarter. Yellow Umbrella Quilts answers quilt counts and care in its fat quarter FAQs. Pelenna Patchworks lists metric cuts in its fabric buying guide.
Video tutorial
"What is a Fat Quarter vs. A Quarter Yard of Fabric?" by National Quilters Circle, on YouTube. The video loads only when you press play.