Precut Quilt Calculator

How many 5 inch squares per quilt size

The table uses common finished quilt sizes and a plain grid of squares with ¼″ seams and no border. Every row and column is rounded up, so the finished top can come out a little larger than the target; the last column shows the real size. Charm packs and layer cakes are counted at 42 squares per pack.

There is no single official quilt size chart, and bed quilts vary with mattress depth and how much drop you want. If your pattern or bed is different, type your own width and length into the calculator above.

How the math works

Every precut is sold at its cut size. Once you sew it, a ¼″ seam disappears on each side, so the finished size is the cut size minus ½″:

• Mini charm: 2.5″ cut → 2″ finished
• Charm square: 5″ cut → 4.5″ finished
• Layer cake square: 10″ cut → 9.5″ finished

Then it is just division. Columns = quilt width ÷ finished square, rows = quilt length ÷ finished square, both rounded up to a whole square. Squares needed = columns × rows, and packs = squares ÷ 42, rounded up. If you add a border, take twice the border width off both the width and the length first, because the border sits on both sides.

The most common mistake is dividing by 5 instead of 4.5. On a queen that gives 18 × 22 = 396 squares, and the quilt comes out about 9″ narrower and 9″ shorter than planned.

Worked example: a queen quilt from charm packs

1. Target: 90″ × 108″ finished, no border.
2. Finished square: 5″ − ½″ = 4.5″.
3. Columns: 90 ÷ 4.5 = 20. Rows: 108 ÷ 4.5 = 24. Both divide evenly, so the top finishes at exactly 90″ × 108″.
4. Squares: 20 × 24 = 480.
5. Packs: 480 ÷ 42 = 11.4, so buy 12 charm packs (504 squares) and keep 24 spares for swapping out prints you dislike.

Now add a 6″ border. The pieced center shrinks to 78″ × 96″, which is 18 × 22 = 396 squares and 10 charm packs. The center finishes at 81″ × 99″, so the quilt ends up 93″ × 111″ with the border. Drop the border to 4.5″ if you need to hit 90″ × 108″ exactly.

Layer cakes, jelly rolls and fat quarters

Layer cakes. One 10″ square finishes at 9.5″, so you need about a quarter as many pieces as with charms. A queen takes 120 squares, or 3 layer cakes. You can also cut each layer cake square into four 5″ squares, so one layer cake gives 168 charm squares, the same as four charm packs.

Jelly rolls. A jelly roll has 40 strips, each 2.5″ × about 42″. The calculator treats them as horizontal rows sewn end to end, allowing 40″ of usable length per strip once the selvages are trimmed. Each strip finishes 2″ wide, so a 60″ × 70″ throw needs 35 rows, about 53 strips, and 2 jelly rolls. A queen needs 54 rows and about 123 strips, so 4 rolls. Leave a little extra for the diagonal joins.

Fat quarters. A fat quarter is 18″ × 22″; plan on 18″ × 21″ after trimming the selvage. That yields 12 five-inch squares, 2 ten-inch squares or 56 mini-charm squares per fat quarter. The 224-square throw above takes 19 fat quarters, and the queen takes 40.

Tips before you cut and sew

• Directional prints. Precut squares are cut in all directions from the bolt, so text, trees and animals can end up sideways. Sort them upright before you sew and buy an extra pack if many are directional.
• Pinked edges. Most charm packs and layer cakes have zigzag pinked edges. Measure your ¼″ seam from the outer points, not the valleys, or every square will finish small.
• Pressing. Press seams in alternating directions row by row so the intersections nest and the corners line up without pins.
• Scrappy mixing. Packs from one fabric line include repeats. For a scrappier queen, mix two or three coordinating lines and lay the squares out on the floor or a design wall before you sew rows together.
• Prewashing. Do not prewash precuts. Small squares fray and shrink unevenly; if you worry about dye bleeding, use a colour catcher in the first wash of the finished quilt.