How To Make Half Square Triangles Eight at a Time with Printable Size Chart
Learn the quick and accurate way to make half-square triangles using the eight-at-a-time method! This easy quilting tutorial walks you through each step, including cutting, sewing, and trimming tips for perfect HSTs every time.
If you’ve ever made a quilt with lots of half-square triangles (HSTs), you know how much work is involved. These versatile little blocks form the foundation for many classic quilt designs, including pinwheels, stars, chevrons, and more.
When your pattern calls for dozens (or hundreds!) of HSTs, it can feel like a chore. That’s where the eight-at-a-time half square triangle technique comes to the rescue! It’s fast, efficient, and keeps your pieces beautifully consistent.
What is a Half Square Triangle (In Quilting)
A half-square triangle, or HST, is one of the most common and essential quilt units. It’s made up of two right triangles joined along the diagonal to form a square. Usually, it’s one-half light fabric and one-half dark.
By rotating or combining HSTs in different ways, you can create everything from bold geometric designs to soft, traditional star blocks. Because of their versatility, mastering HSTs (making them quickly and accurately) is a must for every quilter.
(Baby quilt made using only half square triangles – free tutorial on our site)
What Is the Eight-at-a-Time Method?
The 8-at-a-time method is precisely what you think it is. You sew and cut just two squares of fabric, and end up with eight matching half-square triangles. It’s a simple way to save time without sacrificing accuracy.
This method works well for patterns that require multiple identical HSTs, such as star quilt blocks or flying geese quilts.
Bonus: Printable Half Square Triangle Size Chart
Once you get the hang of this method, you can use our reference chart listing your favorite finished HST sizes and the corresponding square sizes to cut. You’ll save time on future projects and always get accurate results.
To get a printable copy of the chart, simply fill out the form below, and we will email it to you.
Note: if you don’t see the form and blue submit button, please let us know which device and browser you are using. A few people have mentioned that they can’t see the form, but we cannot replicate the error on our end. To fix it, we need to be able to reproduce it. Your specific feedback is helpful!
What You’ll Need
The fabric in this example is from Bluegrass Charm and is available in our shop.
Before you start, gather a few basic quilting tools:
- Two fabric squares (the same size); see size chart for exact sizes
- Rotary cutter and ruler
- Fabric marking pencil, chalk, or Frixion pen
- Sewing machine with ¼” presser foot
- Iron and pressing mat
Eight at a Time Half Square Triangle Technique
Equipment
supplies
- 1/2 yard Fabric A Exact yardage required will be determined by how many half square triangles you are making and the specific size.
- 1/2 yard Fabric B Exact yardage required will be determined by how many half square triangles you are making and the specific size.
Instructions
Cut:
- From Fabric A:1 Square (exact size of the square is found on the printable size chart).
- From Fabric B:1 Square (exact size of the square is found on the printable size chart).
Step One: Mark the Fabric
- Draw an X diagonally on the wrong side of the lighter square of fabric.
Step Two: Pin
- Pin one marked fabric square with one square from a 2nd fabric, right sides facing.
Step Three: Sew
- Ensure you know the 1/4″ seam mark on your sewing machine foot. For these steps, stitching exactly 1/4″ on each side of the line is essential.
- Stitch 1/4″ on each side of the line you drew in both directions.
Step Four: Cut
- You are now ready to cut your square into eight smaller pieces. Using your rotary cutter and quilt ruler, make four cuts.
- First, cut a line horizontally across your block precisely in the center. Next, make a vertical cut also in the center.
- The last cuts are made diagonally along the line you drew in step one.
Step Five: Press & Trim
- You should now have eight pieces of fabric. Open up the HSTs and press the seam towards the darker fabric.
- Trim up each sewn HST to the size noted in the chart.
Why Trimming Your Half-Square Triangles Matters
Taking the time to trim your half-square triangles is one of the easiest ways to improve the accuracy of your quilting. Even a small bit of shifting or stretching while sewing can make your blocks slightly uneven, and when you multiply that across an entire quilt, those tiny differences add up.
Trimming ensures that each HST is perfectly square and the same size, which means your points will line up beautifully when you start joining blocks.
When you use the eight-at-a-time method, your units are intentionally made slightly larger than needed. This extra bit of fabric provides you with room to square up each piece precisely, allowing you to trim away any uneven edges or excess threads.
It’s a small step that makes a big difference. Your seams will match more easily, your blocks will lie flatter, and your finished quilt will look clean and professional.
Why Quilters Love This Method
The eight-at-a-time technique is one of the most efficient ways to make HSTs, especially when you’re working with precuts or scrap fabric. Here’s why you’ll love it:
- Fast: Make eight blocks in the time it usually takes to make two.
- Accurate: Fewer seams to handle means less distortion.
- Flexible: Works with any fabric combination or size.
It’s perfect for large quilt projects, sampler blocks, or anywhere you need lots of matching HSTs quickly.
Ready to Try It? Next time your quilt pattern calls for a mountain of HSTs, try the eight-at-a-time method; it’s fast, fun, and practically foolproof.
