Intarsia (knitting)

The inside of the same argyle sock, showing the lack of carried strands, and the twist at each change of colour

Intarsia is a knitting technique used to create patterns with multiple colours. As with the woodworking technique of the same name, fields of different colours and materials appear to be inlaid in one another, fit together like a jigsaw puzzle.

Unlike other multicolour techniques (including Fair Isle, slip-stitch colour, and double knitting), there is only one "active" colour on any given stitch, and yarn is not carried across the back of the work; when a colour changes on a given row, the old yarn is left hanging. This means that any intarsia piece is topologically several disjoint columns of colour; a simple blue circle on a white background involves one column of blue and two of white—one for the left and one for the right. Intarsia is most often worked flat, rather than in the round. However, it is possible to knit intarsia in circular knitting using particular techniques.

Common examples of intarsia include sweaters with large, solid-colour features like fruits, flowers, or geometric shapes. Argyle socks and sweaters are normally done in intarsia, although the thin diagonal lines are often overlaid in a later step, using Swiss darning or sometimes just a simple backstitch.