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FiberTools

Blanket Yarn & Size Calculator

Knitting & Crochet

Calculate blanket stitch counts and estimate yarn from a measured swatch for sizes from baby to king.

What is this?

A blanket yarn calculator that scales the yarn used by your own swatch to a selected blanket size, then calculates stitch counts, rows, total yards, and whole skeins.

Who needs it?

Knitters and crocheters planning a blanket project who want to buy the right amount of yarn before starting.

Bottom line

Choose a throw, queen, or custom size, then enter a measured swatch and the yarn-label length and weight to calculate yards and whole skeins.

Blanket Size

Your Gauge (optional, for stitch counts)

Swatch yarn used (for yardage)

Make the swatch in your actual stitch pattern, then weigh it. The calculator scales that measured use to the blanket area.

Enter both values exactly as printed on your yarn label. The result includes a 10% planning buffer and rounds skeins up.

Throw

Calculated target size: 50 × 60 in

Yarn weight: 4 – Worsted

Selected project output

Throw blanket Base size: 50 × 60 in Added overhang: 0 in; pillow tuck: none. Calculated target: 50 × 60 in Stitch and row counts not calculated: enter complete valid gauge. Yarn-estimate size basis: 50 × 60 in target rectangle; not rebased to the selected modeled size. Yarn estimate not calculated: supply measured swatch consumption and yarn-label inputs. Pattern offsets include only your entered extra. No inferred edges, borders or ease; modeled size is not guaranteed.

Enter the swatch dimensions and grams used to calculate yarn and skeins. Gauge alone cannot measure yarn consumption reliably.

Enter complete measured stitch and row gauge for planning counts.

Formula and calculation method

Target width = selected preset or custom width + twice the entered overhang. Target length = selected preset or custom length + entered overhang + 20 inches when pillow tuck is enabled. The 20-inch tuck equals 50.8 centimeters; metric dimensions are converted to inches internally.

Stitches = target width times measured stitches per inch, rounded to a whole stitch. Rows = target length times measured rows per inch, rounded to a whole row. With a stitch multiple and extra, the count is adjusted to the nearest supported multiple-times-repeat-count plus extra, with at least one complete repeat. Turning chains are not added.

Planned grams = swatch grams times target rectangle area divided by swatch area, times 1.10 for the displayed 10% allowance. Planned length uses the actual label length per gram. The whole-skein result rounds upward. Yarn scaling uses the target rectangle, not a new area inferred from rounded stitch counts.

Worked example

Select Queen at 90 by 100 inches and enter 10 inches of additional overhang. The target becomes 110 by 110 inches: add 20 to width and 10 to length. Enabling pillow tuck adds another 20 inches to length, making 110 by 130 inches. At a measured 4 stitches and 5 rows per inch, that target gives 440 stitches and 650 rows before any stitch-repeat adjustment.

Assumptions and limitations

  • Treating a finished-blanket preset as a mattress measurement. The Queen preset begins at 90 by 100 inches; its 60 by 80-inch mattress description is context, not the calculation base.
  • Adding drape twice. The overhang field adds to the selected preset or custom dimensions. Leave it at zero when those dimensions already include the intended drop.
  • Using unmeasured skein or swatch values. Replace the example label values with the actual yarn label before using the yarn estimate.

References

  1. 1. Craft Yarn Council, Standard Yarn Weight System (guideline gauge, needle, and hook ranges). craftyarncouncil.com
  2. 2. Calculation method: finished area ÷ swatch area × measured swatch grams × 1.10 buffer; yarn-label length and weight convert grams to yards and whole skeins.

Frequently Asked Questions

How big should a throw blanket be?

The calculator uses 50×60 inches (127×152cm) as a common throw planning preset. Measure the intended recipient or space, or follow the pattern dimensions, before buying yarn.

How many chains do I need for a throw blanket?

It depends on your yarn weight and gauge. At a measured 4 stitches per inch, 50 inches gives 200 stitches before repeat adjustments. The required starting chain also depends on the stitch pattern and whether turning chains count; this tool does not add those chains.

How much yarn do I need for a baby blanket?

There is no single reliable amount for every baby blanket. Enter the intended dimensions and weigh a swatch made with the actual yarn and stitch pattern to calculate yards and skeins.

What is pillow tuck?

Pillow tuck adds extra length (about 20 inches) to the top of a bed blanket so it can fold over the pillows for a finished look. Toggle it on in our calculator for bed-sized blankets.

Next step

Use the whole-skein count as the yarn quantity, enter its price per skein, and add any notion or extra amounts you want included in the material subtotal.

Total the entered materials

Project-ready supplies

Use your calculated yardage and chosen yarn weight to compare materials before ordering a full dye lot.

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