Cozy Stitchery
What a charm pack, layer cake, jelly roll or fat quarter actually makes
Precuts are sold by the piece, but patterns are written by the unit: squares, strips, half-square triangles. This sheet converts one into the other so you can see before buying whether a bundle stretches to the quilt you want. Yields assume 42 pieces in square packs and 40 strips in a jelly roll, which is common but not universal, so count yours.
| Precut and method | Yield per piece | Yield from 42 pieces | Finished unit | Your count |
|---|---|---|---|---|
| Charm (5 in) cut into quarters | 4 x 2 1/2 in squares | 168 | 2 in squares | |
| Charm paired with a 5 in background square, HST 2 at a time | 2 HSTs | 84 | 4 1/8 in exact, or trim to 4 in | |
| Charm sewn edge to edge, 6 x 7 layout | 1 square | 42 | Top 27 x 31 1/2 in | |
| Layer cake (10 in) cut into quarters | 4 x 5 in squares | 168 | 4 1/2 in squares | |
| Layer cake paired with a 10 in background square, HST 8 at a time | 8 HSTs | 336 | 4 1/8 in exact, or trim to 4 in | |
| Layer cake sewn edge to edge, 6 x 7 layout | 1 square | 42 | Top 57 x 66 1/2 in |
HST 2 at a time finishes at the square size minus 7/8 in: 5 minus 7/8 is 4 1/8 in. HST 8 at a time finishes at (square minus 1 3/4) divided by 2: (10 minus 1.75) / 2 is 4 1/8 in. Pinked edges: follow the pattern on whether to measure from the points or the valleys.
A 2 1/2 in strip about 42 in long, subcut. Pieces per strip is 42 divided by the length, rounded down.
| Subcut length | Pieces per strip | From 40 strips | Finished unit | Your count |
|---|---|---|---|---|
| 2 1/2 in | 16 | 640 | 2 in squares | |
| 4 1/2 in | 9 | 360 | 2 x 4 in rectangles | |
| 6 1/2 in | 6 | 240 | 2 x 6 in rectangles | |
| 8 1/2 in | 4 | 160 | 2 x 8 in rectangles |
| Step | Example | Your roll |
|---|---|---|
| Strips sewn end to end (40 x 42 in) | About 1,680 in | |
| Fold in half and sew along the long edge, repeat 5 times | 1,680 / 32 = 52.5 in long | |
| Strips across after 5 folds | 32 | |
| Width (32 x 2 in finished) | 64 in | |
| Approximate top before trimming | About 50 x 64 in, after seam and end losses |
The joining seams and trimmed ends take a little length, so the top usually finishes slightly under the arithmetic. Add borders to reach a larger size.
Yields assume 18 x 21 in for a fat quarter and 9 x 21 in for a fat eighth. Pieces equal rows times columns, each rounded down.
| Square cut size | From a fat quarter | From a fat eighth | Your count |
|---|---|---|---|
| 2 1/2 in | 7 x 8 = 56 | 3 x 8 = 24 | |
| 3 1/2 in | 5 x 6 = 30 | ||
| 4 1/2 in | 4 x 4 = 16 | ||
| 5 in | 3 x 4 = 12 | 1 x 4 = 4 | |
| 6 1/2 in | 2 x 3 = 6 | ||
| 10 in | 1 x 2 = 2 |
Many fat quarters measure under 18 x 21 in after prewashing and squaring. Measure before counting on the last row of squares.
| Unit the pattern needs | How many | Precut that yields it | Yield per bundle | Bundles needed | Extra yardage |
|---|---|---|---|---|---|
Precuts and the tools that trim them
Square rulers in the precut sizes make trimming HSTs fast, and a spare blade keeps cuts clean through stacked layers.
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