Yarn yardage calculator
Open Yarn yardage 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": "yarn-yardage-calculator",
"category": "calculators",
"built": true,
"requirements": "Up to 10,000 identical pieces, 1 million stitch/row counts and 200% allowance. Rectangular fabric estimate; shaping, cables, color work and finishing are not automatically inferred.",
"implementation": {
"fields": [
{
"key": "swatchWidth",
"label": "Measured swatch width",
"value": 10,
"type": "number",
"min": 0,
"max": 1000000000,
"step": "any"
},
{
"key": "swatchHeight",
"label": "Measured swatch height",
"value": 10,
"type": "number",
"min": 0,
"max": 1000000000,
"step": "any"
},
{
"key": "swatchUnit",
"label": "Swatch dimension unit",
"value": "cm",
"type": "select",
"values": [
"mm",
"cm",
"m",
"in",
"ft",
"yd"
]
},
{
"key": "swatchWeight",
"label": "Yarn weight in the measured swatch",
"value": 5,
"type": "number",
"min": 0,
"max": 1000000000,
"step": "any"
},
{
"key": "weightUnit",
"label": "Swatch weight unit",
"value": "g",
"type": "select",
"values": [
"g",
"kg",
"oz",
"lb"
]
},
{
"key": "mode",
"label": "Target size input",
"value": "Target dimensions",
"type": "select",
"values": [
"Target dimensions",
"Target stitches and rows"
]
},
{
"key": "targetWidth",
"label": "Target width per piece",
"value": 50,
"type": "number",
"min": 0,
"max": 1000000000,
"step": "any",
"showWhen": {
"mode": [
"Target dimensions"
]
}
},
{
"key": "targetHeight",
"label": "Target height per piece",
"value": 60,
"type": "number",
"min": 0,
"max": 1000000000,
"step": "any",
"showWhen": {
"mode": [
"Target dimensions"
]
}
},
{
"key": "targetUnit",
"label": "Target dimension unit",
"value": "cm",
"type": "select",
"values": [
"mm",
"cm",
"m",
"in",
"ft",
"yd"
],
"showWhen": {
"mode": [
"Target dimensions"
]
}
},
{
"key": "swatchStitches",
"label": "Stitches in measured swatch",
"value": 20,
"type": "number",
"min": 1,
"max": 1000000,
"step": 1,
"showWhen": {
"mode": [
"Target stitches and rows"
]
}
},
{
"key": "swatchRows",
"label": "Rows in measured swatch",
"value": 28,
"type": "number",
"min": 1,
"max": 1000000,
"step": 1,
"showWhen": {
"mode": [
"Target stitches and rows"
]
}
},
{
"key": "targetStitches",
"label": "Stitches in each target piece",
"value": 100,
"type": "number",
"min": 1,
"max": 1000000,
"step": 1,
"showWhen": {
"mode": [
"Target stitches and rows"
]
}
},
{
"key": "targetRows",
"label": "Rows in each target piece",
"value": 168,
"type": "number",
"min": 1,
"max": 1000000,
"step": 1,
"showWhen": {
"mode": [
"Target stitches and rows"
]
}
},
{
"key": "pieces",
"label": "Identical pieces",
"value": 1,
"type": "number",
"min": 1,
"max": 10000,
"step": 1
},
{
"key": "extra",
"label": "Extra material allowance (%)",
"value": 10,
"type": "number",
"min": 0,
"max": 200,
"step": "any"
},
{
"key": "ballWeight",
"label": "Weight per ball or skein",
"value": 100,
"type": "number",
"min": 0,
"max": 1000000000,
"step": "any"
},
{
"key": "ballWeightUnit",
"label": "Ball weight unit",
"value": "g",
"type": "select",
"values": [
"g",
"kg",
"oz",
"lb"
]
},
{
"key": "ballLength",
"label": "Length per ball or skein",
"value": 200,
"type": "number",
"min": 0,
"max": 1000000000,
"step": "any"
},
{
"key": "ballLengthUnit",
"label": "Ball length unit",
"value": "m",
"type": "select",
"values": [
"mm",
"cm",
"m",
"in",
"ft",
"yd"
]
}
],
"input": false,
"live": true,
"background": false,
"presentation": "metrics",
"note": "Scale yarn use from a weighed swatch in the same stitch pattern and gauge. Estimate different fabrics or colors separately, then include your own finishing allowance. 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
Estimate yarn length and whole balls from a weighed swatch, target dimensions or stitch counts and the yarn label.
How to use Yarn yardage calculator
- Enter your measurements, rates or supplied recipe.
- Review the quantities, rounding and plan details.
- Download the result and verify it against your actual materials or a sample.
Useful next steps
Weigh the measured fabric
Use a prepared swatch in the same yarn and stitch pattern. Its weight should belong to the measured area; large tails or unmeasured borders distort the estimate. Enter either target physical dimensions or counts based on the swatch gauge.
Scale weight, then use label length
A 10 × 10 cm swatch weighing 5 g scales to 150 g for a 50 × 60 cm rectangle. A 10% allowance gives 165 g. If the yarn label says 200 m per 100 g, that is 330 m and two whole balls.
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.