Half Square Triangle Calculator
The Half Square Triangle Calculator is essential for quilters and patchwork crafters. Automatically calculates starting square sizes needed to create perfect HSTs using 2-at-a-time, 4-at-a-time, and 8-at-a-time methods. Includes mathematical formulas, fraction conversion, cutting and trimming tips. Perfect for quilting projects, quilts, pillows, and craft work requiring precision and fabric efficiency.
2 at a time
Pros:
- Simplest math
- Zero fabric waste
- Great for beginners
Best for: Few HSTs or small projects
4 at a time
Pros:
- More efficient than 2-at-a-time
- Good for medium projects
Cons:
- Bias edge cuts can stretch
Best for: Projects with moderate HST quantities
8 at a time
Pros:
- Maximum efficiency
- Perfect for large projects
- Significant time savings
Best for: Quilts with many identical HSTs
Important Notes
Finished vs Unfinished: Finished size is after sewing into your project. Unfinished size is how you trim HSTs (always 0.5" larger).
Trimming Tip: Always trim HSTs 0.5" larger than desired finished size to allow for accurate trimming.
Rounding Note: For 4-at-a-time method, always round up to nearest 1/4". For other methods, round to nearest 1/8".
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