Fabric consumption per garment calculator
Fabric needed per garment and per dozen from a marker, with shrinkage and wastage allowances that are stated rather than hidden in a single fudge factor.
How this is calculated
net = marker length ÷ garments per marker. Shrinkage that happens after cutting is compensated by dividing: with shrinkage = net ÷ (1 − shrinkage%), because a panel that must measure L after an s% shrink has to be cut at L ÷ (1 − s). Wastage is then added: total = with shrinkage × (1 + wastage%). Weight per garment, if width and GSM are given, is total × width × GSM.
Worked example. A 6.0 m marker holds 4 garments: net 1.5 m. With 3% wastage and no shrinkage: 1.5 × 1.03 = 1.545 m per garment (18.54 m per dozen). With 3% shrinkage as well: 1.5 ÷ 0.97 × 1.03 = 1.593 m.
Questions
- Why use the marker rather than the pattern area?
- The marker already includes the gaps between pattern pieces - its efficiency - which a pattern-area calculation has to guess. If you have a CAD marker, its length per garment is the most reliable consumption you can get before cutting.
- When should I enter shrinkage?
- Only when the marker has been made to the finished dimensions and the fabric will shrink afterwards, for example in a garment wash. If the pattern has already been graded up for shrinkage, enter 0 or you will count it twice.
- What does the wastage allowance cover?
- Losses the marker does not show: end loss at each end of the lay, splicing, fabric faults cut out, and short ends. 2-5% is common; use your own cutting-room records.
Sources & verification
The marker method and the allowance structure follow standard cutting-room and garment-costing practice; the shrinkage compensation is the algebra of the ISO 3759 / ISO 5077 dimensional-change definition. The worked example is recomputed in the automated tests.