Fabric Calculator: Yardage, Seam Allowance & Quilting Tools
I’ve stood in enough fabric stores doing yardage math on my phone’s calculator app, guessing at seam allowances, and buying either too little or embarrassingly too much fabric, to know exactly what a tool like this needs to do. This isn’t one calculator, it’s nine, covering the actual questions that come up across a real sewing or quilting project: how much fabric to buy, how to convert between widths, how seam allowance affects your cut size, and the quilt-specific math that pattern envelopes rarely explain clearly.
What's Included
Fabric Yardage — Enter your piece dimensions and quantity, get the exact yardage to buy, including a waste allowance.
Quilt Fabric — Figure out how many blocks your quilt needs and the fabric to cut them, based on finished size and block size.
Quilt Backing — Calculate backing yardage and how many fabric widths you’ll need to seam together, with a longarm-standard overhang built in.
Quilt Binding — Total binding fabric needed, including strips to cut and extra for mitred corners and joins.
Bias Binding — Work either direction: find how much continuous bias binding a fabric square yields, or find the square you need for a specific length.
Fabric Cost — Total your fabric spend including tax and shipping, with a price-per-metre breakdown for comparing listings.
Seam Allowance — Convert between finished size and cut size for any seam allowance, and reverse the calculation when you already have a cut piece.
Fabric Width Converter — See how much yardage you actually need when switching between fabric widths, useful when your pattern was written for 44″ but the fabric you love only comes in 54″.
Measurement Converter — Quick conversion between inches, centimetres, feet, yards, and metres for any sewing measurement.
A Few Honest Notes on Accuracy
These calculators use standard, non-directional fabric assumptions. If you’re working with a striped, plaid, or heavily directional print that needs pattern matching, add extra to the result, typically 10 to 20% depending on the repeat size. The tools tell you this at the relevant calculator, but it’s worth remembering across the board.
The Quilt Fabric calculator specifically assumes a simple single-fabric square block layout. It doesn’t account for sashing, borders, or multi-fabric piecing, for those, treat the block count as your starting point and add fabric separately for the extras.
None of these replace the exact yardage requirement printed on a commercial pattern, which accounts for every individual piece in that specific design. Use these tools for planning, budgeting, and quilting math that patterns don’t cover, and confirm against your actual pattern once you’ve chosen one.