Mosaic Blanket Size: Calculate Width and Height from Your Swatch

November 2, 2026

AI-created crochet inspiration: blanket size planning

KATHWOOL JOURNAL · Updated November 2, 2026

To estimate a mosaic blanket’s size, multiply its worked stitch count by your measured stitch width, and its row count by your measured row height. Calculate the two dimensions separately. The outer border is an additional measurement.

The two formulas

Body width = worked stitches across × sample width ÷ sample stitch count.

Body height = pattern rows × sample height ÷ sample row count.

Keep your units consistent. If you measure the sample in centimeters, the result is in centimeters. To convert centimeters to inches, divide by 2.54.

A worked example using Acorn Cottage Autumn

This design’s Mosaic chart is 240 stitches by 341 rows, with two side stitches at each edge. The worked width is therefore 244 stitches. If the specified 20-stitch by 20-row sample measures 10 by 10 cm:

Width: 244 × 10 ÷ 20 = 122 cm, about 48 inches.
Height: 341 × 10 ÷ 20 = 170.5 cm, about 67.1 inches.

These dimensions describe the body including its side stitches, before the outer finishing border. They are an example based on a particular sample measurement, not a fixed size for every maker.

What if the sample is not square?

Suppose the same 20 stitches measure 10 cm across, but the 20 rows measure 9 cm high. The estimated width stays 122 cm; the height becomes 341 × 9 ÷ 20 = 153.45 cm. Using the width measurement for both calculations would overestimate the height.

Follow the measuring instructions for the selected technique. A Tapestry sample is not a substitute for a Mosaic sample, even if the two files describe a similar picture.

Allow room for the finishing border

A 3 cm border added outside every edge increases the overall width by about 6 cm and the height by about 6 cm. In the first example, that would give approximately 128 by 176.5 cm. Your actual border construction and finishing may differ; measure rather than forcing the fabric to a target.

Compare the result with something you own

Measure a throw that fits your chair, lap or sofa comfortably. Compare both dimensions with your estimate. If the picture is too large, choose a smaller chart or sample a different yarn setup. Cropping arbitrary rows or columns can remove part of the artwork and break its construction.