Beginner block
Half-square triangles quilt pattern
A queen-size half-square triangles quilt is 86″ × 110″: 130 8″ blocks and a 3″ border. It takes 11⅜ yd of fabric for the top and binding, plus 7⅞ yd of 42″ fabric for the backing. Two triangles sewn into a square: the most useful unit in patchwork. Turned one way and another, the same squares make zigzags, diamonds and stars.
How much fabric for a half-square triangles quilt
The same quilt in three sizes, with a 3″ border and 2½″ binding. Yardage is for 42″ of usable width after trimming selvages, rounded up to the next ⅛ yard with a little extra.
| Throw | Queen | King | |
|---|---|---|---|
| Finished size | 62″ × 70″ | 86″ × 110″ | 110″ × 110″ |
| Blocks | 7 × 8 = 56 | 10 × 13 = 130 | 13 × 13 = 169 |
| White (half-square triangles) | 2 yd | 4¾ yd | 6⅛ yd |
| Navy (half-square triangles, border, binding) | 3¼ yd | 6⅝ yd | 8⅛ yd |
| Top and binding | 5¼ yd | 11⅜ yd | 14¼ yd |
| Backing (42″ fabric) | 4 yd | 7⅞ yd | 9⅞ yd |
| Binding | 7 strips 2½″ × WOF | 11 strips 2½″ × WOF | 12 strips 2½″ × WOF |
| Batting | 70″ × 78″ (twin) | 94″ × 118″ (king) | 118″ × 118″ (king) |
Cutting for one half-square triangles block
Four half-square triangle units (HSTs), made two at a time. All sizes include ¼″ seam allowances. Half-square triangles are made two at a time: cut squares the finished size plus ⅞″, pair a light and a dark, sew ¼″ each side of the diagonal and cut apart.
| Fabric | 4″ block | 6″ block | 8″ block | 10″ block | 12″ block |
|---|---|---|---|---|---|
| Light | 2 squares 2⅞″, cut once on the diagonal | 2 squares 3⅞″, cut once on the diagonal | 2 squares 4⅞″, cut once on the diagonal | 2 squares 5⅞″, cut once on the diagonal | 2 squares 6⅞″, cut once on the diagonal |
| Dark | 2 squares 2⅞″, cut once on the diagonal | 2 squares 3⅞″, cut once on the diagonal | 2 squares 4⅞″, cut once on the diagonal | 2 squares 5⅞″, cut once on the diagonal | 2 squares 6⅞″, cut once on the diagonal |
Block diagram
- A Light (White)
- B Dark (Navy)
Download the block diagram (SVG)
Prints sharp at any size. Use it to plan colours with pencils, or as a pressing guide.
Questions
How much fabric do I need for a queen half-square triangles quilt?
About 11⅜ yd for the top and binding (4¾ yd of white, 6⅝ yd of navy), plus 7⅞ yd of backing. That is for 86″ × 110″ with 8″ blocks, planned on 42″ of usable fabric width with a little extra.
What size is a half-square triangles block?
It is drawn on a 2 × 2 grid, so it works best at 4", 6", 8", 10", 12" finished. 8" is the most common size.
Is half-square triangles good for beginners?
Yes. It uses simple triangle units, and the seams are straight.
Can I use this pattern for free?
Yes. Half-square triangles is a traditional block in the public domain. The diagram and yardage on this page are free; the designer lets you change colours, size and borders and see the new yardage.
Updated November 9, 2026