About Hem & Thimble

Hem & Thimble is a free collection of sewing and quilting calculators and reference charts, built for anyone from a first-time sewist threading a machine for the first time to an advanced maker calculating backing yardage for a queen-size quilt.

Every calculator here is built around real, verifiable sewing math and standard industry conventions — seam allowance and cut-size relationships, pattern grading rules, quilt backing and binding formulas, and the fabric/needle/thread pairings sewists rely on every day. Reference charts (needle sizes, thread weights, stitch lengths) reflect widely-used, manufacturer- and community-standard figures rather than any one brand's proprietary numbers.

I also run Hook & Gauge (crochet/knitting calculators), Feed and Speed (machining calculators), Filament and Layer (3D printing calculators), and Flour and Scale (baking calculators) — same idea, different hobby each time: real math a pattern, a spec sheet, or a recipe won't just hand you, turned into a tool instead of a spreadsheet.