Corner-to-corner grows on the diagonal, one block at a time, and a graphed C2C afghan is just a pixel grid. Measure one block from your swatch; the grid, the increase and decrease rows, and the yarn all follow.
Your Block and Blanket
Your Blanket Is
3,000blocks
50 × 60 blocks · 109 diagonal rows
Increase every row to 50 blocks, hold (increase one end, decrease the other) through row 60, then decrease home.
- Increase rows1–50
- Hold one edge51–60
- Decrease rows61–109
- Yarn + 5% border1,260 g · 2,772 yd
- 100 g skeins13 · buy 14
The Formulas
grid = (width ÷ block) × (length ÷ block) · diagonal rows = across + down − 1increase until the short side’s count, run the long side, decrease homeC2C rows run diagonally, so a 50 × 60 blanket’s longest row crosses the full short dimension. A rectangle increases to the short side’s block count, holds (increasing one end, decreasing the other) for the difference, then decreases out.
Worked Example
A 50 × 60 throw, blocks measuring 1 in and weighing 0.4 g (from a 25-block swatch), 220 yd/100 g yarn:
- Grid: 50 × 60 = 3,000 blocks; diagonal rows: 50 + 60 − 1 = 109.
- Rows 1–50 increase, 51–60 hold one edge, 61–109 decrease.
- Yarn: 3,000 × 0.4 g = 1,200 g, plus 5% for the border → 1,260 g, about 2,772 yd: 13 skeins, buy 14.
How to Measure a Block
- Swatch 5 × 5 blocks, measure the middle diagonal pitch, divide by the blocks crossed: edge blocks mislead.
- Weigh the swatch, divide by 25 for the per-block grams; tiny numbers prefer big samples.
- Graphgans: your pixel chart’s dimensions are the grid: this page sizes the blanket those pixels make at your block.
Assumptions and Defaults
- Classic dc C2C (ch 6 start, 3-dc blocks); hdc C2C makes smaller blocks and denser fabric, the measured block absorbs the difference.
- Yarn total adds 5% for the border row most C2Cs wear.
- Color-change charts spend extra ends to weave: bobbin count is the real cost of a detailed graphgan.
C2C Questions, Answered
How many rows is a C2C blanket?
A C2C blanket has blocks across plus blocks down minus one rows, counted on the diagonal, which comes to 109 rows for a 50 × 60 grid of 1 in blocks. Until you reach the first corner, each row is one block longer than the row before it.
How big is one C2C block?
One C2C block measures whatever your hook, yarn, and tension produce, and worsted double crochet blocks commonly come close to an inch. Measure a swatch before you start, because a difference of a tenth of an inch per block changes a blanket’s width by about five inches.
When do I start decreasing in C2C?
In a square C2C piece, you start decreasing after the single corner, when the row number equals the side count. A rectangle grows until it reaches the short side’s count, then increases at one end while decreasing at the other until the long side is complete, and finally decreases at both ends; the row plan above marks both corners for you.
How much yarn does a C2C graphgan take?
A C2C graphgan takes the block count times the grams per block from your weighed swatch, split by color according to the chart’s pixel counts. Keep the 5% allowance for the border, and expect a little more for bobbins and woven-in ends, which use more yarn than most plans account for.