What a float is
In stranded colourwork, sometimes called Fair Isle style knitting, you carry two colours across each row. When you knit with colour A, colour B travels loosely along the back of the work until it is needed again, and the other way round. Those loose strands on the wrong side are floats.
Floats are not a flaw; they are what gives stranded fabric its warmth and slightly thicker body. The goal is simply to keep them:
- the right length, so they do not snag,
- the right tension, so the front lies flat, and
- evenly spread, so the fabric behaves the same everywhere.
The length rule of thumb
There is no official standard, but the most common guideline is to catch any float longer than about 2.5 cm (1 inch), and many knitters use 5 stitches as a quick alternative. Modern Daily Knitting suggests catching a float at about the middle of any run longer than an inch, and notes that grabby, non-superwash wool can go a little longer because the floats cling to the fabric. At a typical worsted-weight gauge of 20 stitches per 10 cm, those two figures match: five stitches are about 2.5 cm wide. With finer yarn, five stitches are narrower, so some knitters allow seven or more; with chunky yarn, even four stitches can make a long float.
Where floats matter most:
| Item | Why it matters |
|---|---|
| Mittens and gloves | Fingers catch on loose strands every time you put them on |
| Socks | Toes catch on floats and the fabric needs to stretch |
| Children’s garments | Small fingers and buttons snag easily |
| Hats and yokes | Usually more forgiving, but long floats still pull |
| Blankets and cushions | The back is often hidden or lined, so a little more length is acceptable |
How long are the floats in real charts?
We measured every float in the colourwork charts in our library: for each colour in each row, the stitches between one of its stitches and the next.
- Floats measured
- 2,465in 16 colourwork patterns, 194 rows
- Longer than 5 stitches
- 14%345 floats would need catching by the 5-stitch rule
- Longest float
- 23 stitchesEight-point star knitting chart
- Rows with 3+ colours
- 9%candidates for duplicate stitch
Catching long floats
When a design has a long stretch of one colour, you catch (or trap) the unused yarn partway along, so the float is split into two shorter ones.
- Work to roughly the middle of the long stretch.
- Bring the floating yarn over the working yarn, knit the next stitch with the working yarn as usual, then return the floating yarn to its original position.
- Continue to the end of the stretch.
The method varies a little depending on whether you hold one yarn in each hand or both in one hand, but the idea is the same: the float is wrapped once around the working yarn so it is held against the back of the fabric.
Tips for invisible catches
- Stagger them. If you catch in the same column on several rounds, the catches can line up into a faint visible line. Shift each catch a stitch or two.
- Catch behind the same colour. A catch tends to peep through more when the float colour differs strongly from the stitch in front of it.
- Do not over-catch. Catching every two or three stitches makes the fabric stiff and the back bulky.
Keeping tension even
Tight floats are the most common colourwork problem. Before changing colours, spread the stitches you have just worked along the right needle so they sit at their natural width. Then carry the new colour across. The float should lie flat against the back without pulling.
Other habits that help:
- Hold the colours consistently. Many knitters find that the colour carried below the other appears slightly more prominent on the front. Choose one colour as dominant (often the pattern colour) and always hold it the same way.
- Try working inside out. Some knitters turn their work inside out on circular needles, so the floats travel around the larger circumference and naturally get a little more slack.
- Swatch and block. A swatch in the round shows you how your floats behave before you commit to a whole garment.
Why a gauge-correct chart matters
Here is something that catches many people out when designing their own colourwork. Knitted stitches are not square. At a typical gauge of 20 stitches and 28 rows per 10 cm, each stitch is about 5 mm wide but only about 3.6 mm tall, a width-to-height ratio of 7 : 5. Our gauge guide shows the effect side by side.
If you draw a design on square graph paper, the knitted version will be squashed vertically. A 60 × 60 square chart would knit up about 30 cm wide but only about 21 cm tall, so a circle becomes an oval and a face looks flattened. To get a design that looks square when knitted at that gauge, you need roughly 60 stitches by 84 rows.
The knitting colourwork pattern generator uses cells shaped to your gauge. The default is 20 stitches × 28 rows per 10 cm, and you can change it to match your own swatch. A photo converted at your gauge will keep its proportions, and the Realistic view shows each stitch as a knitted V so you can see the effect before casting on. If you prefer to sketch by hand, use graph paper drawn to knitting proportions, such as knitter’s graph paper for worsted weight, rather than square grid paper.
Designing for good floats
The best way to manage floats is to design them out before you start. When you create or edit a chart:
- Look for long horizontal runs. In the Chart view, any stretch of more than five or six stitches of one colour will create a float in the other colour.
- Break up big blocks. A small background “peerie” motif or a scattering of single stitches across a large plain area gives the floats somewhere to be caught naturally.
- Limit colours per row. The generator can use up to 20 colours, which is useful for intarsia-style pictures or duplicate stitch, but for stranded work check that no row needs more than two or three at once.
- Clean up isolated stitches. Confetti cleanup removes lone stitches that would otherwise create awkward short floats and fiddly colour changes.
The knitting editor is handy for this last step. Use the pencil to add catch points into long plain runs, the line tool to draw a row of contrast stitches, or the mirror options to make a symmetrical motif.
Following the written rows
Every knitting PDF from CraftPatterns includes written row instructions alongside the chart. For flat knitting, right-side rows are read from right to left and wrong-side rows from left to right, matching the way the work comes off the needle. If you are knitting in the round, every round is a right-side round, so many knitters simply read every row of the chart from right to left. Checking each row for float lengths before you start it takes seconds and saves a lot of tinking back.