A year is 365 rows, and at most gauges that blanket runs past seven feet. Enter your gauge and width; you get the starting count, the true length of every row plan, and the yarn, split across your colors.
Your Gauge and Size
Craft
One Row per Day Runs
91in long
315 stitches across · 70 × 91 in at one row per day
- Starting stitches315
- One row per day91 in long
- One row per two days46 in long
- A week averaged per row13.3 in long
- Yarn for the full yearabout 6,000 yd · 28 skeins of 220
- Per color, buying ceilingabout 600 yd
The Formulas
length = rows ÷ row gauge · one row per day: rows = days · one per two days: rows = days ÷ 2starting stitches = width × stitch gauge · yarn scales by the blanket's areaThe whole craft of a temperature blanket is squeezing 365 days into a blanket-shaped number of rows. Thin rows, paired days, or weekly averages all work; check each plan against the length math above.
Worked Example
Moss-stitch crochet at 18 stitches and 16 rows per 4 in, 70 in wide, 365 days, 10 colors:
- Start: 70 × 4.5 = 315 stitches across.
- One row per day: 365 ÷ 4 = 91 in long: the classic 70 × 91 year. One row per two days: 46 in, a wide throw. A week averaged per row: 52 rows, about 13 in, a table runner of a year.
- Yarn at 70 × 91: about 6,000 yd in this open stitch: 28 skeins of 220. Across 10 colors that’s a 600 yd ceiling each, and the middle temperatures use the most: buy the extreme colors last, once winter’s lows are known.
How to Measure Your Inputs
- Swatch the actual stitch in the actual yarn: temperature blankets live or die on row gauge, and a half row per inch moves the year by a foot.
- Width is a choice, length is arithmetic. Pick the width for the bed; the row plan is what controls length.
- Colors: most keys run 8 to 12 bands. Fewer bands mean longer color runs and fewer ends to weave; more bands mean a smoother gradient and a bigger yarn order.
Assumptions and Defaults
- Yarn totals scale the published afghan ranges by your blanket’s area, with the crochet allowance applied on the crochet setting; open stitches run under the figure, dense texture over.
- The per-color split divides evenly and reality won’t: mild-weather bands do most of the work. Treat the split as a shopping ceiling per color.
- Day-per-square pixel plans (C2C or granny grids) are grid math, not row math: the C2C calculator handles those.
Temperature Blanket Questions, Answered
How many stitches do I start a temperature blanket with?
A temperature blanket starts with its width times your stitch gauge per inch, so 70 in at 4.5 stitches per inch starts on 315 stitches. Swatch the exact stitch you plan to use first, because moss stitch, hdc, and ripple gauges differ more than their names suggest.
How long will a temperature blanket of 365 rows be?
A temperature blanket of 365 rows is the days divided by your rows per inch long, so at 4 rows per inch a year runs 91 in, and at 6 rows per inch about 61 in. If that is too long, work one row for every two days, average each week into a row, or turn the blanket sideways and work the days as columns.
How much yarn does a temperature blanket take?
A temperature blanket takes yarn according to its size rather than its calendar, so a 70 × 91 in worsted blanket uses about 5,500 to 6,500 yd in a solid stitch, and less in open stitches. The calculator scales the total to your blanket and splits it across your number of colors.
How many colors should a temperature blanket key have?
A temperature blanket key usually has eight to twelve colors, which covers most climates in 5 degree bands. Check your town’s record low and high for the year, stretch the key to cover both, and buy the most yarn for the middle bands, since most days fall there.