Knitting Needle Sizes and Conversion Chart

Knitting needle sizes can sometimes be confusing. Different countries have their own unique ways of numbering knitting needles, which can make it difficult to determine the right size for your project.

In this comprehensive guide, I’ll provide you with all the information you need to understand knitting needle sizes. Whether you’re trying to convert metric sizes to US needle sizes or simply looking for the best size for beginners, I’ve got you covered. Discover why needle size matters and find the perfect size for the yarn you are using.

Let’s take the guesswork out of finding the perfect knitting needle size and ensure your projects turn out beautifully. But first, get ready to convert the knitting needle sizes into your preferred measurements!

This post features affiliate links. If you use these links to buy something I may earn a commission at no additional cost to you. As an Amazon Affiliate I earn from qualifying purchases.

Wooden circular needles and double pointed needles next to two skeins of yarn

Knitting Needle Size Chart

Discover the ideal knitting needle sizes for your projects with this handy conversion chart. It provides a clear comparison between metric, US, and UK sizing systems, ensuring you select the perfect needles every time.

You can download and print your personal copy of this cheat sheet here and keep it in your knitting project bag.

Metric SizeUS SizeUK Size
1 mm0000019
1.25 mm000018
1.5 mm00017
1.75 mm0015
2 mm014
2.25 mm113
2.5 mm(1 ½)
2.75 mm212
3 mm(2 ½)11
3.25 mm310
3.5 mm4
3.75 mm59
4 mm68
4.5 mm77
5 mm86
5.5 mm95
6 mm104
6.5 mm10 ½3
7 mm2
7.5 mm1
8 mm110
9 mm1300
9.5 mm14
10 mm15000
12 mm17
16 mm19
19 mm35
20 mm36
25 mm50
Knitting needle sizes chart for metric, US, and UK sizes.

Needle Sizes Around the World

Knitting is popular worldwide, and knitting needle sizes can vary depending on where you are. Understanding the different knitting needle size systems used around the world is essential for knitters who explore patterns and sources from various countries.

Let’s take a closer look at the diverse systems you may encounter.

Metric System (mm): In many countries, including those in Europe as well as in Australia and New Zealand, knitting needle sizes are measured in millimeters (mm). The metric system provides precise measurements, making it easier to match the recommended needle size to the project’s requirements.

US System: The United States has its own knitting needle sizing system. In this system, needle sizes range from 00000 (1 mm) for the smallest to 50 (25 mm) for the the largest. The US system is known for its wider range of sizes, catering to different project needs and yarn thicknesses.

UK System: In the United Kingdom, knitting needle sizes are numbered in the opposite direction compared to the US system. The sizes start from 19 (1 mm) for the smallest needles and progress up to 000 (10 mm) for the largest. The UK system is also used in Canada.

Japanese System: Japan employs its own unique knitting needle size scale. Ranging from 0 for the smallest needles to 15 for the largest, this numerical system is used in Japanese knitting patterns. It’s important to note that the Japanese system may have slight variations compared to other sizing systems.

Two metal straight needles showing a blue end cap with a 6.5mm knitting needle size marking
In the metric system, knitting needle sizes are measured in millimeters (mm).

Japanese Needle Size Chart

Japan has its own unique knitting needle size system that doesn’t match the same metric sizes as US and UK needles. This needle sizes chart shows the conversion from metric measurements to Japanese knitting needle sizes.

Metric SizeJapanese Size
2.1 mm0
2.4 mm1
2.7 mm2
3.0 mm3
3.3 mm4
3.6 mm5
3.9 mm6
4.2 mm7
4.5 mm8
4.8 mm9
5.1 mm10
5.4 mm11
5.7 mm12
6 mm13
6.3 mm14
6.6 mm15
Knitting needle conversion chart for metric and Japanese sizes.

Understanding Knitting Needle Sizes

Knitting needle sizes refer to the thickness or diameter of the needles used in knitting. They are typically measured and indicated by a numerical system, where a larger number usually indicates a larger diameter. The only exception is the UK system where it goes the opposite way.

The size of the knitting needles directly affects the stitch size, tension, and overall appearance of the knitted fabric. The larger the needle size, the larger the stitches and resulting fabric, while smaller needle sizes produce tighter stitches and a denser fabric.

Choosing the right knitting needle size is crucial for achieving the desired gauge or tension specified in a knitting pattern. The recommended needle size will vary depending on factors such as the yarn weight, desired drape, and the knitter’s individual tension. It’s important to match the needle size with the yarn weight to ensure that the stitches are neither too loose nor too tight.

Understanding knitting needle sizes allows knitters to create projects that meet their desired specifications, maintain consistent stitch sizes, and achieve the intended look and feel of the finished item.

A purple knitting project worked on wooden double pointed needles
If you tend to knit loose, you may need to use smaller needles to achieve the desired tension.

Choosing the Right Knitting Needle Size

Choosing the right knitting needle size is essential for achieving the desired results.

Here’s how to select the appropriate needle size:

Read the yarn label: Yarn labels, also called yarn wraps or ball bands, usually indicate the recommended needle size or a range of sizes for that particular yarn weight. Choose a needle size within that range as a starting point.

Consider yarn weight: If the yarn label is missing, you can find out the needle size based on the yarn weight you’re using. Different yarn weights require different needle sizes for optimal results. Thicker yarns generally require larger needles, while thinner yarns work best with smaller needles. Read more about knitting needle sizes for yarn in the next chapter.

Check the pattern: Start by referring to the knitting pattern—if you’re using one. Most patterns will provide a recommended needle size or a gauge to achieve. Follow the pattern’s guidance as a starting point.

Make a gauge swatch: Knit a gauge swatch using the chosen needle size. This involves knitting a small sample measuring at least 4×4 inches (10×10 cm) to determine the number of stitches and rows per inch. Check the detailed instructions for knitting a gauge swatch here. If your stitch and row counts match the pattern’s gauge, congratulations! You’re using the correct needle size. If not, adjust the needle size accordingly.

  • Too many stitches/rows per inch: Your gauge is too tight. Switch to larger needles to create looser stitches.
  • Too few stitches/rows per inch: Your gauge is too loose. Switch to smaller needles to create tighter stitches.

Consider your personal tension: If you tend to knit tightly, you may need to use slightly larger needles to achieve the pattern’s gauge. Conversely, if you have a looser tension, smaller needles may be necessary. Experiment with different sizes to achieve the desired tension and fabric drape.

Lavender colored skein of yarn showing the label with recommended knitting needle sizes
US size 4 to 8 (3.5 to 5 mm) needles are perfect for knitting with this Aran weight yarn.

Knitting Needle Sizes for Yarn

This chart provides needle size recommendations for various yarns. The common names associated with each yarn weight category are mentioned, along with the corresponding recommended needle sizes.

Please note that these are general recommendations, and it’s always a good idea to check the yarn label or pattern instructions for specific needle size recommendations for your project.

In addition, depending on the tightness or looseness of your knitting, you may need to use a different size knitting needle to get the same gauge as the pattern says. So, always knit a gauge swatch to see if you need to opt for a larger or smaller size needles.

Yarn Weight CategoryCommon Yarn NamesNeedle Size
0: LaceThread, Cobweb, Light FingeringUS 00 to 1 (1.75 to 2.25 mm)
1: Super FineFingering, Baby, SockUS 1 to 3 (2.25 to 3.25 mm)
2: FineBaby, SportUS 3 to 5 (3.25 to 3.75 mm)
3: LightDK, Light WorstedUS 5 to 7 (3.75 to 4.5 mm)
4: MediumWorsted, Afghan, AranUS 7 to 9 (4.5 to 5.5 mm)
5: BulkyChunky, Bulky, Craft, RugUS 9 to 11 (5.5 to 8 mm)
6: Super BulkySuper Chunky, RovingUS 11 or up (8 mm or up)
7: JumboRovingUS 17 or up (12 mm or up)
Knitting needle sizes for different yarns.

How To Know the Size of Your Needles

A bunch of mysterious knitting needles laying around in a drawer is common phenomenon among knitters. So how to identify their sizes?

Most commercial needles are clearly labeled with their size. However, these markings often wear off after awhile and the size is no longer visible on the needle itself.

If this is the case, or if the needle didn’t have the size even at the beginning, you have two options for identifying the size of your needles.

Firstly, you can use a normal ruler to measure the diameter of your needle, as long as it uses the metric system. Simply place the wide part of the needle onto the hash marks on your ruler and measure the width of the needle.

A tape measure on top of a knitting needle measuring the size of it in millimeters
If you don’t know the size of your needles, you can use a normal ruler to measure the diameter of your needle.

Secondly, you can use a knitting needle gauge to determine the size. A knitting needle gauge, also called a knitting needle sizer, is a small plastic, wooden, or metal tool with holes of different sizes.

Measuring your needle with the knitting needle gauge is easy. Just insert the needle into the holes until you find the one that matches. You have successfully identified the needle size, when the needle slides in smoothly and sits snugly in the hole.

Personally, I find using a knitting needle gauge to be the easiest and quickest way to do it. In fact, I think every knitter should have one in their toolbox!

Hands holding a sheep shaped knitting needle gauge and measuring the size of a wooden needle
A knitting needle gauge is the easiest and quickest way to measure your needle size.

There are many different kind of knitting needle gauges available to fit every knitter’s liking and needs. This cute sheep shaped knitting needle gauge by HiyaHiya is my top choice! It shows the knitting needle sizes in millimeters on one side and in US sizes on the other. It’s also nice and thick so it doesn’t bend like many other needle gauges.

Knitting Needle Sizes FAQ

Here are answers to couple of common questions I frequently keep asked about.

What size knitting needles for beginners?

Medium-sized needles US 6 to 8 (4 to 5 mm) are usually best for beginners. Small needles require too much precision whereas the really big needles can be awkward to handle. Medium-sized needles, in turn, are easier for beginners to work with as they allow you to see your stitches more clearly and work more quickly.

What size are 4mm knitting needles?

Knitting needles in size 4mm equal to US 6 and UK 8 sizes. In the Japanese system, the closest equivalent is 3.9mm, which converts to 6.

What size knitting needle do I need?

The size of knitting needles needed generally depends on the weight of the yarn. In general, the heavier the yarn, the larger the needles. Lace weight yarn will typically need needles between US 00 to 1 (1.75 to 2.25 mm), worsted or medium-weight yarn will need needles between US 7 to 9 (4.5 to 5.5 mm), and bulky yarn will need needles between US 9 to 11 (5.5 to 8 mm), or even larger.

Can I use 5mm needles instead of 4mm?

Yes, it is generally acceptable to use 5mm needles instead of 4mm needles, but using larger needles may result in slightly larger stitches and a looser fabric. Make a gauge swatch to ensure your new needle size aligns with the pattern. If you’re a tight knitter you just might get away with it, after all, the needle size on the pattern is only a suggestion of what you’ll need to get the correct gauge.

What size knitting needles for regular yarn?

Worsted weight yarn is often considered ordinary or regular knitting yarn. Depending on the desired stitch gauge and your personal tension, you would use US size 7 to 9 (4.5 to 5.5 mm) needles for knitting.

Wooden knitting needles showing the knitting needle size printed on them
Most commercial needles are clearly labeled with their size but these markings often wear off after awhile.

Conclusions

Now you have a better understanding of knitting needle sizes. And with the help of my needle sizes chart, you can confidently navigate different sizing systems and embark on your knitting adventures. No more confusion or guessing games when it comes to finding the perfect needle size for your yarn!

Remember, knitting is all about fun and creativity, so don’t be afraid to experiment and try different needle sizes to achieve your desired results. Whether you’re working on a lace shawl, a cozy sweater, or a chunky scarf, the right needle size can make all the difference in bringing your vision to life.

So grab your yarn, grab your needles, and let your imagination run wild! With the knowledge of knitting needle sizes and the power of conversion charts, you’re equipped to embark on endless knitting adventures. Happy knitting, and may your stitches be even and your projects be fabulous!

Read also: