The tote bag calculator
Sewing your own tote bag is a fantastic beginner project. But, figuring out the math for the fabric cuts—especially when you want a specific finished size and a boxed bottom—can be tricky. Our calculator does this for you instantly.
Simply input your desired finished Height, Width, and Depth, and we'll tell you how big of a piece of fabric you need to cut.
Bag measurement formulas
We use standard sewing formulas to estimate the fabric needed for a "single piece" construction (folded at the bottom).
- Fabric Width: Bag Width + Bag Depth + (2 × Seam Allowance)
- Fabric Length (Total): (2 × Bag Height) + Bag Depth + (2 × Top Hem)
- Box Corners: Bag Depth / 2
For example, if you want a bag that is 12" wide, 14" high, and 4" deep, you'll need a piece of fabric
roughly 17" wide by 34" long (using 0.5" seams and 1" hem).
How can I calculate box corners for a bag?
To give your bag a flat bottom (depth), you need to cut "box corners" out of the folded fabric. The formula is simple:
Box Corner Size = Desired Depth / 2
So for a 4-inch deep bag, you would cut 2-inch squares out of the bottom corners of your folded fabric.
Types of tote bags
You can use this calculator for various styles:
- Market Tote: Usually deep and wide for groceries.
- Book Bag: Flat (0 depth) and tall.
- Beach Bag: Very large with a wide base.