Quilt precut calculator
A queen size quilt takes about 3 jelly rolls, 3 layer cakes, or 35 fat quarters if the top is precuts edge to edge. Enter your quilt size and precut type below for your exact count, with the spare fabric and the assumptions spelled out.
You will need
Precuts at a glance
Every precut is the same quilting cotton in a different haircut. The useful comparison is how much finished quilt each one provides once the 1/4" seams are sewn.
| Precut | Contents | Raw fabric | Finished area provided |
|---|---|---|---|
| Mini charm pack | 42 squares, 2 1/2" | about 1/6 yard | 168 sq in |
| Charm pack | 42 squares, 5" | about 2/3 yard | 850 sq in |
| Fat quarter | one 18" x 21" cut | 1/4 yard | about 250 sq in |
| Jelly roll | 40 strips, 2 1/2" x WOF | about 2 3/4 yards | 3,200 sq in |
| Layer cake | 42 squares, 10" | about 2 3/4 yards | 3,790 sq in |
Notice the quiet scandal in that table: a jelly roll and a layer cake contain the same amount of fabric, but the layer cake delivers nearly 20% more finished quilt, because big pieces lose proportionally less to seams. Small pieces are charming; they are also expensive in seam allowances.
How many precuts for each quilt size
Counts assume the quilt top is precuts edge to edge, the hungriest case. Patterns with sashing, borders, or background fabric need fewer.
| Quilt size | Jelly rolls | Charm packs | Layer cakes | Fat quarters |
|---|---|---|---|---|
| Throw (50" x 65") | 2 (1 makes 50" x 64") | 4 | 1 | 13 |
| Twin (70" x 90") | 2 | 8 | 2 | 26 |
| Queen (90" x 95") | 3 | 11 | 3 | 35 |
| King (110" x 95") | 4 | 13 | 3 | 42 |
Why one jelly roll makes a 50 x 64 quilt
The famous jelly roll race quilt is just this arithmetic wearing a party hat. Forty strips at roughly 40 usable inches each is 1,600 inches of strip; sewn into one long ribbon and folded into rows, that ribbon becomes about 32 rows of 50", each finishing 2" tall, which is a 50" x 64" quilt. Our calculator gives the same answer from the area math, which is a comforting sign that both the racers and the arithmetic are honest.
Sources and methodology
Quilt area = width x length, finished. Finished area per precut: jelly roll strips finish 2" x ~40" usable (3,200 sq in per 40 strip roll); charm squares finish 4 1/2" (850.5 sq in per 42); mini charms finish 2" (168 sq in); layer cake squares finish 9 1/2" (3,790.5 sq in); fat quarters yield roughly 250 finished sq in each after cutting and seams. Units = area / per-precut area, rounded up. Counts assume standard 40 or 42 piece packs; some brands vary. Cross-checked against published quilting references and the standard jelly roll race result.
Precut questions, answered
Three, if the entire top is jelly roll strips: a 90" x 95" queen is 8,550 finished square inches and each roll provides about 3,200. Two rolls plus a generous border from yardage also gets there, and many queen jelly roll patterns are designed exactly that way to save you the third roll.
Two packs for a 40" x 40" baby quilt: 64 charms sewn 8 x 8 finish at 36" square, and 1,600 sq in of quilt divided by 850 per pack lands at 1.9. Two packs leaves you about 20 spare charms, which is the universe suggesting a matching doll quilt.
Because a fat quarter is raw yardage, not a ready-to-sew shape; how much of it survives depends on what the pattern cuts from it. A pattern cutting big 9" setting squares wastes little, while one fussy cutting small motifs may use half. Our 250 finished square inch estimate sits in the realistic middle; treat pattern requirements as the final word when you have them.
Per yard, no; precuts usually cost 20 to 40% more than the same fabric on the bolt. What you are buying is the curation: forty coordinated prints from one collection with no quarter yard commitments to each. For two or three fabric quilts, yardage and our strip calculator beat the precut on price every time.