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Calcimator

Gathering Ratio Calculator

Calculate the fabric length needed for gathered sections based on finished length and fullness ratio. Typical ratios: 1.5× for light, 2× for medium, 3× for heavy gathering.

Inputs

in
×
in

Results

Cut Fabric Length

49.25 in

≈ 8 smartphones

Fabric in Yards1.37 yd
Fabric (no seams)48 in
Extra for Gathering24 in
Gathering Thread2.74 yd
How to Use This Calculator
  1. Enter the finished gathered length (inches) that the fabric must gather down to.
  2. Set the fullness ratio (1.5:1 = light gathering, 2:1 = moderate, 3:1 = full ruffle).
  3. Enter seam allowances (inches) for the gathering and attachment seams.
  4. Review total fabric length to cut before gathering, total yards, and gathering excess.
  5. Check that your machine can gather the selected fabric weight -- heavy fabric requires stronger gathering.

How the result changes with Finished Gathered Length

Finished Gathered LengthCut Fabric Length
1633.25 in
4591.25 in
79159.25 in
108217.25 in

What each input means

Finished Gathered Length
Desired length of the section after gathering
Fullness Ratio
Gathering ratio (1.5×=light, 2×=medium, 2.5-3×=full/ruffled)
Seam Allowances
Total seam allowance at both ends of the gathered section

How this is calculated

Worked example, using the default values

  1. Identify Input Parameters
    Finished Gathered Length = 24, Fullness Ratio = 2, Seam Allowances = 1.25 = 3 input(s) provided
  2. Calculate Cut Fabric Length
    Cut Fabric Length
    49.25 = 49.25
  3. Calculate Fabric in Yards
    Fabric in Yards = round((totalFabricLength / 36) * 100) / 100
    1.37 = 1.37
  4. Calculate Fabric
    Fabric
    48 = 48

Engine last updated . Checked against 2 independently-derived tests — how we verify calculators.

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