Calculators

Make hourglass blocks from quarter-square triangles

The Quarter-square triangles calculator gives the square size for the quick hourglass method, how many squares to cut, and the size to trim each block to.

Where to find it

Studio top bar → Calculators → Quarter-square triangles. Also at quiltler.com → Calculators, and in the Calculators tab of the iPhone and iPad app.

Open the hourglass calculator
On the Quarter-square triangles calculator, typing a 6 inch finished hourglass and 12 blocks gives 6 squares cut at 7 1/4 inches, sewn in pairs and cut on both diagonals, each block trimmed to 6 1/2 inches

How to do it

  1. Press Calculators in the studio's top bar and choose Quarter-square triangles. It opens on eight 4″ hourglass blocks, with the answer already in the You need card.
  2. Type the size you want in Finished hourglass (inches).
  3. Type How many blocks you need.
  4. Read the card: how many squares to cut, the Cut size, and the size to trim each block to.
  5. Pair the squares right sides together, sew all four sides, cut both diagonals, and open four hourglasses from each pair.

Good to know

  • The square is the finished size plus 1¼″, and each block is trimmed to the finished size plus ½″.
Who can use it
Free, no account needed on the web
Where it works
Web studio · quiltler.com · iPhone & iPad

This guide answers

  • What size square do I cut for quarter-square triangles?
  • How do I make hourglass blocks?
  • How many squares for 12 hourglass blocks?
  • What do I trim hourglass blocks to?