happytails.ai

Sewing pattern scale calculator

Open Sewing pattern scale calculator on Happytails.ai. This view has the same page content and links, with explicit tool capabilities. Read the processing notes before using a tool.

Tool capabilities

{
  "id": "sewing-pattern-scale-calculator",
  "category": "calculators",
  "built": true,
  "requirements": "Recommended print scale from 1% to 10,000%. Produces scale instructions and dimensions, not an edited PDF. Large prints may need tiling.",
  "implementation": {
    "fields": [
      {
        "key": "measuredReference",
        "label": "Reference measured on your current print",
        "value": 9.5,
        "type": "number",
        "min": 0,
        "max": 1000000000,
        "step": "any"
      },
      {
        "key": "desiredReference",
        "label": "Reference size required on the new print",
        "value": 10,
        "type": "number",
        "min": 0,
        "max": 1000000000,
        "step": "any"
      },
      {
        "key": "referenceUnit",
        "label": "Reference measurement unit",
        "value": "cm",
        "type": "select",
        "values": [
          "mm",
          "cm",
          "m",
          "in",
          "ft",
          "yd"
        ]
      },
      {
        "key": "previousScale",
        "label": "Custom print scale used for the current print (%)",
        "value": 100,
        "type": "number",
        "min": 1,
        "max": 10000,
        "step": "any"
      },
      {
        "key": "patternWidth",
        "label": "Current printed pattern width",
        "value": 20,
        "type": "number",
        "min": 0,
        "max": 1000000000,
        "step": "any"
      },
      {
        "key": "patternHeight",
        "label": "Current printed pattern height",
        "value": 30,
        "type": "number",
        "min": 0,
        "max": 1000000000,
        "step": "any"
      },
      {
        "key": "patternUnit",
        "label": "Pattern dimension unit",
        "value": "cm",
        "type": "select",
        "values": [
          "mm",
          "cm",
          "m",
          "in",
          "ft",
          "yd"
        ]
      }
    ],
    "input": false,
    "live": true,
    "background": false,
    "presentation": "metrics",
    "note": "Calculate the new absolute print percentage from a measured reference. Print a test with fit-to-page disabled and remeasure before cutting. This does not edit a PDF or grade garment sizes. Changing units keeps the entered numbers. Calculations run on your device.",
    "experience": {
      "automatic": true,
      "single": false,
      "inputMaxLength": 1000000,
      "inputMode": "text",
      "label": "Your text",
      "placeholder": "Type or paste your input…",
      "help": "Change the input or settings to update your result. Results update as you type. Up to 1,000,000 characters.",
      "helpParts": [
        "Change the input or settings to update your result.",
        "Results update as you type.",
        "Up to 1,000,000 characters."
      ],
      "action": null
    },
    "mode": "automatic",
    "interactive": false
  },
  "execution": "Browser interface",
  "api": null,
  "browser_agent": {
    "supported": true,
    "name": "run_current_tool",
    "discovery": "WebMCP on the human page in a supporting browser",
    "verification": "See audit/API-AUDIT.md; availability is not verification"
  }
}

Page guide

Calculate a print percentage from a measured reference and see the expected uniformly scaled pattern dimensions.

How to use Sewing pattern scale calculator
  1. Enter your measurements, rates or supplied recipe.
  2. Review the quantities, rounding and plan details.
  3. Download the result and verify it against your actual materials or a sample.

Useful next steps

Origami paper size calculatorFabric shrinkage calculator

Measure the print you actually have

Enter a reference length measured on the current printed pattern and the intended new reference length. Also enter the custom scale used to produce that print. This accounts for an earlier print that was already enlarged or reduced.

Verify the new reference before cutting

A reference printed as 9.5 cm instead of 10 cm at 100% calls for approximately 105.263% custom scale. Disable automatic fit-to-page and measure the new print in both directions. Uniform scaling also changes seam allowances and does not replace garment grading.

Save the plan

Download the result as CSV, plus a text or JSON report with formulas, values and assumptions. Everything is calculated on your device. Changing units keeps the entered numbers, so check the selected units before using the plan.