How to Measure Knitting Gauge: Swatch, Block and Count in 9 Steps

How to measure knitting gauge, step by step

1. Read the gauge line in the pattern. Note the stitch count, row count, measurement, stitch pattern and needle size, for example 20 sts and 28 rows over 4 in in stockinette on US 8. Check whether the pattern says the gauge is measured after blocking.
2. Cast on enough stitches for a 6 inch swatch. Multiply the pattern stitches per 4 in by 1.5, then add 6 stitches for a garter border of 3 on each side. At 20 sts per 4 in, cast on 36 stitches. The border keeps the edges from curling so you can measure the middle.
3. Knit in the pattern stitch. Knit 4 rows of garter, then work the stitch named in the gauge line, keeping 3 garter stitches at each edge, until the piece is about 6 in tall. Use the exact needles you plan to use for the project, such as tips from the ChiaoGoo Twist Red Lace set.
4. Bind off loosely. Finish with 4 rows of garter and bind off without pulling tight, so the top edge does not draw in the swatch.
5. Wash it like the finished project. Soak the swatch in cool water with a no-rinse wool wash such as Eucalan No Rinse Wash, or machine wash it if the project will be machine washed. Roll it in a towel to press out water without wringing.
6. Block and dry flat. Lay the swatch flat on a mat such as the Knit Picks Blocking Mats, which have a 1 in grid, smoothing it to shape without stretching. Let it dry completely.
7. Unpin and let it rest. Remove any pins and leave the swatch loose for a few hours. A swatch measured while pinned can read smaller than it will behave in a garment.
8. Count stitches and rows over 4 inches. Place a 4 in window such as the Clover Swatch Ruler and Gauge in the center, away from the border. Count the Vs across one row for stitch gauge and up one column for row gauge, counting half stitches. Measure in two or three spots and average them.
9. Compare, adjust and record. If you have more stitches than the pattern, go up a needle size; if fewer, go down a size, then swatch again. Write the yarn, needle size and final gauge on a tag and keep the swatch with the project.

Why is gauge important in knitting?

Because every stitch count in a pattern is really a measurement in disguise. A sweater with a 40 in chest written at 20 stitches per 4 in casts on 200 stitches around the body. Knit those 200 stitches at 18 stitches per 4 in and the chest measures 44.4 in. Knit them at 22 and it measures 36.4 in. That single stitch of difference per 4 in moves the sweater a full size or more.

Gauge also changes how much yarn you use. Looser knitting makes a bigger piece from the same stitches, so a sweater that grows 4 in around also eats more yardage, and knitters who skip the swatch are the ones who run out of a discontinued dye lot three inches from the end.

The math behind the table is simple: width equals stitches times 4, divided by your stitches per 4 in. The cast on calculator does it for any width and gauge, including ribbing multiples.

What is the knitting gauge for worsted weight yarn?

The Craft Yarn Council, the trade group behind the numbered yarn weight symbols on most labels, lists medium weight yarn, which includes worsted, afghan and aran, at 16 to 20 stitches per 4 in on US 7 to 9 (4.5 to 5.5 mm) needles. That is 4 to 5 stitches per inch. Every weight has its own range, and these are the most commonly used sizes, not rules.

The label on your yarn narrows the range further. Vanna's Choice lists 16 stitches and 22 rows on US 9. Basic Stitch Anti-Pilling lists 18 stitches and 26 rows on US 8, and Wool-Ease lists 18 stitches and 24 rows on US 8. Wool of the Andes gives 4.5 to 5 stitches per inch on US 6 to 9, and the super bulky Wool-Ease Thick and Quick lists 9 stitches and 12 rows on US 13. Treat any label as a starting point for your swatch, not a promise. For needle equivalents, see the knitting needle size chart or the page for US 8 (5 mm) needles, and the full profile of medium weight yarn.

How do you read knitting gauge on a pattern?

A gauge line has five parts, and each one matters:

• Stitches, such as 20 sts. This controls width, and it is the number to match first.
• Rows, such as 28 rows. This controls length and the spacing of shaping.
• Measurement, nearly always 4 in or 10 cm. The two are close but not identical: 4 in is 10.16 cm.
• Stitch pattern, such as stockinette, garter, seed stitch or a cable chart. Different stitches make very different gauges on the same needle, so swatch the stitch named. Our page on stockinette stitch covers the most common one.
• Needle size, often followed by "or size needed to obtain gauge." That phrase is permission to change needles.

Watch for two extra words. "Blocked" means the designer measured after washing, so you must too. "Tension" is the UK word for gauge, so a British pattern that lists tension is asking for the same swatch.

How do you use a knitting gauge ruler?

A knitting gauge ruler is a flat card with a cut-out window, usually 2 or 4 in wide, plus a row of holes for checking unmarked needles. Lay the dried swatch on a flat surface, set the window over the middle of the fabric so one edge lines up with the side of a column of Vs, and count the stitches inside the window. Turn the ruler to count rows. The Clover Swatch Ruler and Gauge has a 4 in (10 cm) window with holes for needles and notches for hooks marked in metric, US and Japanese sizes, for about $9. The larger ChiaoGoo Swatch Gauge, about 5.5 in square, adds printed conversion charts and yarn standards tables, and the Susan Bates Knit Chek measures both needles and hooks for about $6.

A few habits make the count honest:

• Push a pin in at the start and end of 4 in before counting, so the fabric cannot shift.
• Count half stitches. Gauge of 18.5 is real and matters on a large piece.
• Count rows on the knit side by the Vs stacked in one column, which is easier than counting purl bumps.

Dark yarn is where counts go wrong. A daylight lamp with accurate color, such as the Daylight Slimline 4 Floor, rated at 6,000K, a CRI of 95+ and 3,200 lux at 30 cm, shows every V in navy or charcoal without squinting.

What if your knitting gauge is off by 1 or 2 stitches?

First, decide which direction you are off, because the fix is the opposite of what feels natural.

There is no fixed conversion between needle sizes and stitches, so always swatch again after a change. A complete interchangeable set makes that painless: the ChiaoGoo Twist Red Lace set covers US 2 to 15 in stainless steel, and the birch Knit Picks Sunstruck set covers US 4 to 11 for about $77. For shaping, the increase and decrease evenly calculator redistributes stitches once you have rescaled a count.

Is knitting gauge different flat vs in the round?

For many knitters, yes. Knitting stockinette flat alternates knit and purl rows, and a lot of people purl a little looser or tighter than they knit. In the round, stockinette is knit stitches only, so the fabric can come out a slightly different gauge from the same needles. If your project is a hat, a sock or a sweater body knit in the round, swatch in the round.

Two ways to do it: knit a small tube on a 16 in circular about 7 in around, then slit it or measure it flat as a double layer, or knit a "speed swatch" flat, working knit rows only and carrying the yarn loosely across the back at the end of each row. Measure only the middle of either one.

Do you measure gauge before or after blocking?

After, unless the pattern specifically says otherwise. Water relaxes the yarn and evens out stitches, and many fibers change size: wool often blooms and softens, superwash wool and many cotton and plant fiber yarns are known for growing in length when wet, and acrylic usually changes the least.

Block the swatch exactly as you will block the project. A set of foam mats like the KnitIQ Blocking Mats, which come with 100 T-pins, gives you a flat surface for the swatch now and the whole sweater later. Compare options in our best blocking mats roundup.