Convert fabric width by checking area and a new layout
A width conversion can preserve area while making a pattern piece impossible to place. Use an area ratio as arithmetic, then check the actual cutting layout on the new width.
For equal rectangular area, new length = old length × old width ÷ new width. The result is not guaranteed yardage for your garment because shapes, direction and gaps still matter.
Exact units and measured width
One inch is 2.54 cm. Therefore 45 inches is 114.3 cm and 60 inches is 152.4 cm. The metric stock widths 115 cm and 150 cm are different values, not exact conversions. In the app, enter the usable width you measured rather than substituting the nearest preset.
| Starting rectangle | Equal-area rectangle | What it means |
|---|---|---|
| 3 yd × 45 in | 2.25 yd × 60 in | The areas match; no pieces have been arranged |
| 2 m × 140 cm | About 2.545 m × 110 cm | 27.27% more length |
| 2 m × 140 cm | About 3.111 m × 90 cm | 55.56% more length |
What a ratio cannot tell you
Suppose a piece must remain in its current direction and is 120 cm wide. It cannot fit a 110 cm usable width as one piece, even if the fabric length is very large. Smaller pieces can also force a different number of rows, changing the unused space.
Conversely, a wider cloth does not guarantee the full proportional length saving. There may be no additional pieces that can use the extra strip alongside the layout.
Do not confuse envelope area with piece area
The old yardage includes the spaces in its stated arrangement and may include allowances or reserves. It is not a measurement of the combined cutting-piece area. Matching that rectangle's area can be too much for one alternative arrangement and insufficient for another.
Compare two complete arrangements
Use the same outlines, quantities, allowances and direction rules for both widths. Record each returned length and inspect placement completeness. If one result is incomplete, it gives no comparable finished layout length.
Prepare and measure the fabric as intended for sewing. Keep shrinkage, unusable edges and print matching separate from the equal-area calculation.
Check the layout in PatternNest
Import closed cutting outlines from SVG, DXF or a supported vector PDF and check their dimensions. Select individual PDF pages; tiled pages are not stitched automatically. For folded fabric, mark the cut-on-fold edge. Use a full unfolded outline when planning that piece on a single layer. Seam allowances are neither added nor removed; exported outer contours do not replace internal markings such as notches or grain arrows.
Orient the pieces according to your sewing pattern before import. Enter usable width, spacing, quantities and mirrored pairs. Grainline mode allows the prepared orientation and a 180-degree turn; one-way mode keeps the prepared orientation. The software does not test stretch or detect the fabric's actual direction.
The calculated length belongs to the returned layout. Check every placement, dimension and allowance before cutting. An incomplete search does not prove that no other arrangement fits. Repeat matching, shrinkage and defects still need a check on the cloth.
Calculation and PDF/SVG/DXF export are free for up to 10 fabric pieces, counting all copies and mirrored pieces. A mirrored pair counts as two. More than 10 fabric pieces require a license for both calculation and export.
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