Granny square calculator
Turn the blanket size and square size into columns, rows, and a total square count.
The finished width differs from the target by 8.0%. Whole squares rarely land exactly on a target. Adjust the square size or accept the drift.
Enter the yardage one square uses to get a total yarn estimate.
Your result
Layout preview: 9 columns by 11 rows, 99 squares total.
Show the math
Lay out 9 columns and 11 rows of 6 in squares, 99 squares total, for a 54 × 66 in finished blanket. Add a yarn-per-square figure to estimate total yarn.
| Usable width | 50 in - 2 × 0 in | = 50 in |
|---|---|---|
| Usable height | 66 in - 2 × 0 in | = 66 in |
| Square + join | 6 in + 0 in | = 6 in |
| Columns | ceil((50 + 0) ÷ 6) | = 9 columns |
| Rows | ceil((66 + 0) ÷ 6) | = 11 rows |
| Total squares | 9 × 11 | = 99 squares |
| Body width | 9 × 6 + 8 × 0 | = 54 in |
| Body height | 11 × 6 + 10 × 0 | = 66 in |
| Finished width | 54 in + 2 × 0 in | = 54 in |
| Finished height | 66 in + 2 × 0 in | = 66 in |
Whole squares only, so counts round up to reach the target. Square size must be measured after blocking.
The general formula
available_width = target_width - 2 × border_width available_height = target_height - 2 × border_width columns = ceil((available_width + join) ÷ (square + join)) rows = ceil((available_height + join) ÷ (square + join)) total_squares = columns × rows body_width = columns × square + (columns - 1) × join body_height = rows × square + (rows - 1) × join finished_width = body_width + 2 × border_width finished_height = body_height + 2 × border_width total_yarn = yarn_per_square × total_squares + border_yarn
What this calculation does not account for
- Square size must be measured after blocking. Squares grow when blocked.
- Join width depends on the joining method you use.
- Squares may not all block to exactly the same size.
- Borders may stretch differently from the square fabric.
- Yarn usage varies by stitch pattern, tension, and finishing.
- This is a layout calculator, not a crochet pattern.
How to use this
- Enter the finished blanket size you want, and any border width you plan to add around the squares.
- Enter your square size from a blocked square worked in your actual yarn and stitch pattern.
- Enter a join allowance if your joining method adds width between squares. Leave it at 0 if unsure.
- Optionally add yarn details to estimate total yardage and skein count.
Related calculators
For a solid, continuous blanket worked in rows instead of squares, use the blanket size calculator. To check your yarn from a swatch, use the yarn estimator.