# Fabric Width Conversion Calculator

> Convert the fabric length a pattern asks for at one width (say 45 in) into the length you need at another width (say 60 in), by equal area.

Category: Textile & apparel · Applies to: Worldwide · Last updated: 2026-10-29
Interactive calculator: https://calculators.geekmidst.com/calculators/fabric-width-conversion-calculator

If the pattern asks for a length at one width and your fabric is wider or narrower, the same area is length × width, so the new length is the old length × old width ÷ new width.

Also called: Fabric yardage converter.

## Inputs
- Length the pattern asks for (default 2.5)
- Length in (options: Yards, Metres; default yd)
- Fabric width in the pattern (default 45)
- Width of your fabric (default 60)
- Widths in (options: Inches, Centimetres; default in)

## Results
- Length needed at your width
- Change in length
- Fabric area

## Formula

```
New length = Original length × Original width ÷ New width
```

Where:
- Original length, width: what the pattern envelope states
- New width: the usable width of the fabric you are buying

## Worked example
1. Area = 2.5 yd × 45 in; at 60 in wide the same area needs 2.5 × 45 ÷ 60 = 1.875 yd.
2. 1.875 ÷ 2.5 − 1 = −25%, so you need a quarter less fabric.

**Result:** 2.5 yards of 45-inch fabric converts to 1.875 yards (about 1⅞ yd) of 60-inch fabric.

## What the result means

Round up to the next cut your shop sells, and add extra for one-way designs, nap, pile or pattern matching, which an equal-area conversion cannot see.

## Assumptions and limits
- Both widths are usable widths, excluding selvedges.
- Pattern pieces can be laid out as efficiently on either width.
- Large pieces that do not fit across a narrow fabric need more length than the area rule suggests.

## Questions

### Is this the same as a fabric conversion chart?

Yes. Printed charts are equal-area conversions rounded up to convenient fractions of a yard.

### Should I add extra?

Add 10–15% for directional prints, velvet or plaid matching, and for pre-wash shrinkage.

## Related calculators
- [Fabric Shrinkage Percentage Calculator](https://calculators.geekmidst.com/calculators/fabric-shrinkage-percentage-calculator)
- [Fabric Consumption per Garment Calculator](https://calculators.geekmidst.com/calculators/fabric-consumption-per-garment-calculator)
- [Length Converter](https://calculators.geekmidst.com/calculators/length-converter)

Source: GM¹X CalcVerse — https://calculators.geekmidst.com/calculators/fabric-width-conversion-calculator