CraftM8 › QuiltM8 › Calculators › Borders
How wide do I cut the borders?
Butted or mitred borders: the cut width with its seam allowances, how many strips, the yardage — and the finished size of the quilt afterwards, which is the number binding and backing want.
Side pieces: 72" · Top and bottom pieces: 66" · Total strip length: 276" · Fabric used: 24 1/2" · Longer than the fabric is wide: no
Show the maths
| 1 | Cut width — 3" + 2 × 1/4" | 3 1/2" |
| 2 | Border pieces — 2 × 72" (sides) + 2 × 66" (top & bottom, over the sides) | 276" |
| 3 | Strips — 276" ÷ 40" → round up | 7 |
| 4 | Fabric to buy — 7 × 3 1/2" = 24 1/2" → round up to the next 1/8 yd | 3/4 yd |
| 5 | Finished size — centre + 2 × 3" each way | 66" × 78" |
Measure through the middle of the quilt, not along the edges. Strips may be joined end to end to reach length.
Where the formula comes from
A 3″ finished border cuts at 3 1/2″ — the border plus a seam allowance each side. Mitred corners need the border width added at each end; the tool carries the allowance so the mitre is never short.
- Butted borders. Sides are attached first at the centre height, then top and bottom span the full new width; cut width is the finished width plus two seam allowances.
- Mitred borders. Every strip must span its side plus both border widths, with extra length for the 45° join; 4" total is the common allowance.
- Pieced vs unpieced strips. Cross-grain strips must be joined for anything longer than the usable width, and some quilters refuse a pieced border on a visible edge. With piecing off, each of the four pieces is costed as its own uncut width of fabric, and the tool says so when a piece is longer than the fabric is wide.
This is the app's own arithmetic running in your browser, put through the same worked examples every time this site is built.
A worked example
The worked example is the how-to quilt: a 3″ butted border on a 60″ × 72″ centre, finishing at 66″ × 78″.
| 1 | Cut width — 3" + 2 × 1/4" | 3 1/2" |
| 2 | Border pieces — 2 × 72" (sides) + 2 × 66" (top & bottom, over the sides) | 276" |
| 3 | Strips — 276" ÷ 40" → round up | 7 |
| 4 | Fabric to buy — 7 × 3 1/2" = 24 1/2" → round up to the next 1/8 yd | 3/4 yd |
| 5 | Finished size — centre + 2 × 3" each way | 66" × 78" |
Works with
- How much binding? — Bind on the finished size this tool reports.
- How much backing? — Back the finished size, not the centre.
In the app, this answer joins a quilt
Save it to a project, add the other tools' answers, and the shopping list totals every fabric with one rounding — then prints a cut sheet for the table. Offline, no account, one payment, yours forever.
In development A closed test on Google Play is the next step.