Count binding after the strips are joined
For straight quilt edges, measure the actual perimeter after quilting and trimming. Add a deliberate working reserve for corners, handling and the final closure. Intermediate strip joins consume length separately.
Worked example below. These fixed measurements are not your calculated cutting plan. The eight strips use 20 in along the bolt. The illustrated optional 1 in for squaring makes 21 in; both round to 5/8 yd. This squaring inch is not a calculator field and is separate from its binding-length reserve.
Count binding after its joins
- Trimmed quilt: 60 x 78 in; perimeter 276 in.
- Add the chosen 15 in reserve: 291 in target.
- Eight 2 1/2 in strips use 20 in of fabric length; add 1 in squaring = 21 in. Buy 5/8 yd (22 1/2 in) at this shop.
Required working length
291 in
276 in perimeter + chosen 15 in reserve.
Seven joined strips
279 in
7 x 42 - 6 x 2 1/2. Short by 12 in.
Eight joined strips
318 1/2 in
8 x 42 - 7 x 2 1/2. Enough for the stated target.
The 15-inch reserve includes the final closure. Intermediate diagonal joins are deducted separately, with one cut strip width lost at each specified ideal overlap. This is straight-grain binding, not bias binding.
A square overlap uses one strip width
- Cut strip width and overlap-square side: 2 1/2 in.
- Each intermediate join in this ideal layout consumes 2 1/2 in of running length.
- Retain 1/4 in between the stitching and trim lines, measured perpendicular to the diagonal.
Stitch, then trim with an allowance
- Square-ended strips are perpendicular before the join is opened.
- Dashed = stitch. Solid diagonal = trim. Hatched = remove. Keep 1/4 in perpendicular to the seam.
- Original strip edges and offset diagonal trim line
- Corner-to-corner stitching; do not cut here
- Removed corner beyond the trim line
Cropped seam detail, drawn to scale across the overlap; the strip ends do not represent full strip lengths. Sew on the dashed diagonal. Trim on the separate solid diagonal, keeping the unhatched 1/4 in seam allowance between them. Only the hatched corner beyond the trim line is removed. This ideal geometry still needs a physical sewing check.
In this example, eight 2 1/2 × 42 in strips provide 318 1/2 in after seven diagonal joins. Their construction length is 20 in along the bolt. The illustrated optional 1 in for squaring makes 21 in; the calculator’s working reserve is binding length, not a separate bolt-squaring field. Both amounts round to 5/8 yd at this selling increment. This is straight-grain double-fold binding, not a method for curved edges.