Quilt top size calculator
4 blocks across and 5 down at 12″, with 2″ sashing and a 4″ border, makes 62 × 76″ of quilt top. Change any number below and watch it recompute.
Your quilt top
- Finished quilt top
- 62 × 76″
- Before the border
- 54 × 68″
- Blockscut 20
- 12½ × 12½″
- Sashing between blocks in a rowcut 15
- 2½ × 12½″
- Sashing between rowscut 16
- 12½ × 2½″
- Cornerstonescut 12
- 2½ × 2½″
- Side borderscut 2
- 4½ × 68½″
- Top and bottom borderscut 2
- 62½ × 4½″
Scroll sideways to inspect every label.
4 blocks across by 5 blocks down. Finished top 62 × 76″ with sashing between blocks; borders shown.
Fabric for a 62 × 76″ top
Scroll sideways to see every column.
| Piece | Cut | How many | Fabric |
|---|---|---|---|
| Blocks | 12½ × 12½″ | 20 | 2½ yd |
| Sashing between blocks in a row | 2½ × 12½″ | 15 | ⅜ yd |
| Sashing between rows | 12½ × 2½″ | 16 | ⅜ yd |
| Cornerstones | 2½ × 2½″ | 12 | ⅛ yd |
| Side borders | 4½ × 68½″ | 2 | not computed |
| Top and bottom borders | 62½ × 4½″ | 2 | not computed |
Every "cut" figure includes the seam allowance; the block size, the sashing width and the border width are all FINISHED sizes. Fabric is based on 40″ of usable width and rounded up to the nearest eighth of a yard, and each row is counted separately so two different fabrics are never ordered as one.
What this does not work out, and why
Border fabric, backing, batting and binding are not worked out here, and the reason is the same for all four: the sources do not agree on how much to allow. Border strips are joined end to end, and a figure that guesses the joins short leaves you with a border that will not reach. Backing and binding vary with who quilts the top and how it is bound. Rather than hand you a number nobody can stand behind, this page stops where the arithmetic is solid.
The border CUT sizes above are exact. It is only the yardage that is left out.
Common layouts
| Layout | Blocks | Sashed between | Sashed all round |
|---|---|---|---|
| 3 across by 4 down | 12 | 48 × 62″ | 52 × 66″ |
| 4 across by 5 down | 20 | 62 × 76″ | 66 × 80″ |
| 5 across by 6 down | 30 | 76 × 90″ | 80 × 94″ |
| 6 across by 7 down | 42 | 90 × 104″ | 94 × 108″ |
Pick a block for your quilt
Each block page gives the fabric for one block, computed at the size you choose.
- Bear's Paw
- Broken Dishes
- Card Trick
- Churn Dash
- Flying Geese
- Friendship Star
- Heart
- Jacob's Ladder
- Log Cabin
- Maple Leaf
- Nine Patch
- Ohio Star
- Pinwheel
- Rail Fence
- Sawtooth Star
- Shoofly
- Sister's Choice
- Square in a Square
Related pages
- Quilt block sizes Compare clean steps, cuttable eighths, and refused sizes.
- 12 inch quilt blocks Compare blocks that divide cleanly at 12 inches.
- Fabric yardage calculator Turn dimensions and quantity into fabric yardage.
Common questions
How big will my quilt be with 20 twelve-inch blocks?
Twenty blocks lays out as four across by five down, and at 12″ finished with no sashing that is 48 × 60″ of quilt top. Sashing and borders grow it from there — put your own numbers into the calculator above and read the exact size.
How wide should sashing be?
There is no rule — sashing width is a design choice, and published quilts range from a whisper to wider than the blocks. Proportion is the guide: wide sashing floats the blocks apart, narrow sashing keeps them talking. Type a width in and look at the finished size; the arithmetic is free.
Does this include the seam allowance?
Yes, on the correct side of every number: the sizes you TYPE are finished sizes, and every CUT size in the table already includes the seam allowance. Enter what you want the quilt to measure, cut what the table says.
How much backing do I need?
This calculator deliberately does not work backing out — the allowance depends on who quilts the top, and the published figures disagree too widely to pass one off as fact. What it does give you is the finished top size, which is the number every backing decision starts from; take it to your longarmer or your favourite method's instructions.