# Pattern Piece Area Calculator

> Find the area and perimeter of a pattern piece from its outline points, then the fabric area and length for an order at your fabric width and marker efficiency.

Category: Textile & apparel · Applies to: Worldwide · Last updated: 2026-10-29
Interactive calculator: https://calculators.geekmidst.com/calculators/pattern-piece-area-calculator

Trace a pattern piece’s outline as corner points and the shoelace formula gives its exact area. Multiply up for the order and divide by width × marker efficiency for fabric length.

Also called: Garment pattern area calculator.

## Inputs
- Outline points (x, y) (default 0, 0
50, 0
45, 70
5, 70)
- Measurements in (options: cm, inches; default cm)
- Pieces per garment (default 2)
- Garments (default 1000)
- Cuttable fabric width (default 150)
- Marker efficiency (unit %; default 80)

## Results
- Piece area
- Piece perimeter
- Area per garment
- Total pattern area
- Fabric length needed

## Formula

```
Area = ½ |Σ (xᵢ·yᵢ₊₁ − xᵢ₊₁·yᵢ)|;  Total = Area × Pieces × Garments;  Length = Total ÷ (Width × Marker efficiency)
```

Where:
- xᵢ, yᵢ: outline corners in order (1 in = 2.54 cm)
- Marker efficiency: pattern area ÷ marker area

## Worked example
1. The outline is a trapezoid: (50 + 40) ÷ 2 × 70 = 3,150 cm².
2. Two pieces per garment × 1,000 garments = 6,300,000 cm² = 630 m².
3. Length = 630 ÷ (1.5 m × 0.80) = 525 m.

**Result:** Each piece is 3,150 cm², and 1,000 pairs need about 525 m of 150 cm fabric at 80% marker efficiency.

## What the result means

Use the total area to estimate fabric before a marker is made, and to compare a marker’s efficiency once it exists.

## Assumptions and limits
- Points are in order around the outline and the outline does not cross itself.
- Curves are approximated by straight lines between points; add more points along curves for a closer area.
- Seam allowances must be included in the outline you trace.

## Questions

### Does the starting corner matter?

No. Any start point, clockwise or anticlockwise, gives the same area.

### What marker efficiency should I use?

Your CAD system’s figure for similar styles; it depends on the pieces, sizes and fabric width.

## Related calculators
- [Fabric Lot Quantity Calculator](https://calculators.geekmidst.com/calculators/fabric-lot-quantity-calculator)
- [Fabric Wastage Percentage Calculator](https://calculators.geekmidst.com/calculators/fabric-wastage-percentage-calculator)
- [Area Calculator](https://calculators.geekmidst.com/calculators/area-calculator)

Source: GM¹X CalcVerse — https://calculators.geekmidst.com/calculators/pattern-piece-area-calculator