Quilt Block Calculator
Count blocks across and down for a target size, with between-block sashing and outer sashing kept separate.
Calculator
Calculated in your browser. These measurements are not sent to the server.
Result
- Blocks
- 5 across × 5 down (25)
- Actual finished size
- 50 in (127 cm) × 50 in (127 cm)
No sashing is included. Block count is the target size divided by the finished block size, rounded up.
The actual finished size can be larger than the target because block counts round up.
Cut sizes add the same seam allowance to both edges of a finished width. Sashing length is the finished length of that piece.
Piece count
PieceBlocks
Count25
Cut width10.5 in (26.67 cm) × 10.5 in (26.67 cm)
PieceBetween-block vertical sashes
Count0
Cut width—
PieceBetween-block horizontal sashes
Count0
Cut width—
PieceInner cornerstones
Count0
Cut width—
PieceOuter sides
Count0
Cut width—
PieceOuter top and bottom
Count0
Cut width—
PieceOuter corners
Count0
Cut width—
| Piece | Count | Cut width |
|---|---|---|
| Blocks | 25 | 10.5 in (26.67 cm) × 10.5 in (26.67 cm) |
| Between-block vertical sashes | 0 | — |
| Between-block horizontal sashes | 0 | — |
| Inner cornerstones | 0 | — |
| Outer sides | 0 | — |
| Outer top and bottom | 0 | — |
| Outer corners | 0 | — |
How this calculation works
With no sashing, blocks across are the target width divided by the finished block width, rounded up. The actual quilt can end up larger than the target.
Between-block sashing uses n = ceil((target + sashing) ÷ (block + sashing)). The actual width is n blocks plus sashing only in the gaps.
Outer sashing is removed from the target before that count, then added back around the inner grid. It is not treated as another between-block strip.
Worked example
42 in target, 10 in blocks, 2 in between-block sashing
n = ceil((42 + 2) ÷ (10 + 2)) = 4 blocks.
Actual width = 4 × 10 + 3 × 2 = 46 in.
The same 2 in added as outer sashing instead of only between blocks produces a different finished size.
Assumptions and limitations
- Block size and sashing widths are finished sizes.
- Seam allowance is used only for the optional cut width of a block or sash strip.
- Between-block sashing and outer sashing are separate fields.
- On-point settings, partial blocks, and cornerstones of a different fabric are counted, but their yardage is not optimized.
- Sashing is not described as one optional value with an undefined position.
Common questions
Why can the finished quilt be larger than the target?
Block counts round up. The result shows the actual finished size so you can adjust the target or the block size.
What is the difference between the two sashing fields?
Between-block sashing sits only in the gaps. Outer sashing is a frame around the grid. Using one number for both would hide that choice.