Professional sewing maths · clear enough to learn from

Measure clearly.
Cut confidently.

Clean, visual calculators that respect fabric width, construction allowances, store increments and the way sewists actually measure—in US fractions or UK/metric units.

Calculate fabricPlan a circle skirt
01US fractions

28 ⅜ in


02UK / metric

72.1 cm


03Store rounding

2.6 m → 2.7 m

Millimetres internallySelvedges excludedAccessible diagramsNo account required
Complete sewing toolkit

One visual language across every calculation.

Start with the answer. Open the construction detail only when you need it.

01

Fabric quantity

Six true shapes, optimised layouts, reverse yield and usable-width planning.

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02

Circle skirt

Fabric purchase, radii, fold topology, panel fallback and a separate interactive guide.

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03

Quilt binding

Perimeter, actual diagonal joins, pattern matching and crosswise strips.

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04

Bias binding

A corrected continuous-bias square that covers estimated join losses.

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05

Curtains

Drops, fullness, hems, returns, overlap, seams and pattern repeats.

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06

Print scale

Correct a PDF sewing pattern from its printed test square.

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Learn the foundations

Understand the cloth, then trust the number.

How much fabric do I need?Layout, direction, allowances and store rounding →Fabric widths and selvedgesNominal width versus usable cutting width →Seam allowance explainedFinished lines, cutting lines and common mistakes →
Built for trust

The picture must agree with the number.

  1. 01Usable width means usable width. Selvedges stay outside the calculated cutting area.
  2. 02Internal precision, practical display. Full precision is preserved while measurements are presented like sewing measurements.
  3. 03Honest limits. Geometric planning is never presented as industrial nesting or an automatic printable pattern.