Learn how to sew two half square triangles at a time. It requires two pieces of fabric the same size and you’re ready to go! Follow the video tutorial + printable to make them perfect.
You’ll need to have 2 pieces of fabric for the half square triangles. These need to be somewhat contrasting.
You can use a light / dark or a background fabric with another fabric. The square will turn out identical, the only thing affecting it would be the print of the fabric.
Be aware that using a stripe fabric, the stripes will change direction when the half square triangle is finished.
Materials:
Half Square Triangle Cheat Sheet (found in the Quilters Resource Library- instructions for access at the bottom of the post)
- Bloc Loc ruler for squaring up
- Rotary cutter or a new sharp blade
- Cutting Mat
- Quilt Ruler
- Sewing Machine this brother is my favorite!
- Iron here or here
- Thread
- Bobbins
- Scissors
- Seam Ripper not my favorite thing to do!
2 Half Square Triangles at a time- Tutorial
1- Cut your two pieces of fabric the same size. Use the printable to figure out what size your square need to be.
Find your finished size, then cut the square to the appropriate size prior to starting
2- Draw a diagonal line on the wrong side of the background or lighter fabric from corner to corner
3- Sew on BOTH sides of the drawn line 1/4″ seam allowance – Leave your needle in the down position at the end so you can pivot the fabric easily and return on the opposite side

4- Cut on the drawn line
5- Open the half square triangle and press to the darker fabric
6- Square up the half square triangles to the correct measurement. Don’t skip this step! I use the Bloc Loc Rulers– love them!
More info on the half square triangle – all 4 methods and a calculator that you can use to customize your size!
2-at-a-time Half Square Triangle Calculator
Finished Size: 2″
Cut 2 Squares: 2.875″ each
(Makes 2 HST units)

2 Half Square Triangles at a time- Video
Half Square Triangle Printable
This is a super important part of the process and not one that should be overlooked. There have been some pretty major quilt fails for me when I first started quilting- and it was all because I refused to square up my blocks. That was not fun and in fact those blocks are still haunting me! I really need to move them along to something else!
To help you not have as many issues as I did, here’s a quick video on how to square them up.
How to Square Up Half Square Triangles
Quilt Projects using half square triangles
Sparklers Mini Quilt
Snowman Pillow Tutorial
Chevron Quilt Tutorial

Have a trick for squaring up or making half square triangles? Share it in the comments below-
Becky Jorgensen is the creative quilter behind Patchwork Posse, the Patchwork Planner and her online quilt group Patchworkers Plus. You can find her patterns in books, magazines, and her quilt membership. Gather your quilting supplies, organize your sewing space, explore the process of disappearing quilt blocks, or finish a free quilt pattern. I'll help you use what you have, finish what you start and make your quilting journey fun!
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