Choosing The Correct Yarn, Needle & Hook sizes For Knitting & Crochet

Over the years I have learnt to knit and crochet, I have had to research what yarn could be used for a particular project. It took me time trying to work out terms like what “worsted” meant.  So to make it easier and quicker here is a breakdown of what yarn is used for on certain hooks and needles.




This will be a great help and is something that you will always be able to come back too. Here is a breakdown to help you understand, I have added names for USA, UK and Australia/NZ to help you along the way.


USA UK Australia

& NZ

 Purpose Needle size (mm) Hook Size


 Lace  2 ply  2 ply This is super light weight yarn and is ideal for intricate projects.

For this yarn it is best to use small needles and hooks

 1.25mm – 3.0mm  0.75-3.0mm
 Sock/ Fingering  3 ply  3 ply  This yarn is great for baby clothing including toys.  2.0mm – 3.5mm  2.25-3.5mm
 Fingering/Sports  4 ply  4 ply  This yarn is also suitable baby clothing and lighter weight knits  3.25mm  2.5 – 3.5mm
 Light Worsted  Double Knitting  8 ply Also known as “DK”. This is the most popular choice of yarn.

This is a very versatile yarn as it is cost effective and quick to knit.

 3.5mm-4.5mm  3.5-4.5mm
 Worsted  Aran  10 ply  This is also a quick yarn to knit with and is ideal for the following; sweaters, cardigans.  3.75mm-4.5mm  5.5mm-6.5mm
 Chunky  Bulky  16 ply  This is great for knitting with larger needles and is perfect for rugs  5.5mm-8.0mm  6.5mm-9.0mm
 Bulky  Chunky  20 ply  This is yarn is thick and it easy and quick to finish your project.  8.0mm and above  9.0mm & above
 Jumbo  Super Chunky  This yarn is great for beginners as it is thick and chunky and mistakes will be noticed quickly.  12.75 mm and above  15mm and above



Helpful Notes:

♦ This is a guide, so please always check the pattern or yarn instructions.

♦ Always check tension as this could make a huge difference.




Here are some Frequently Asked Questions on yarn meanings.

What does yarn weight mean?
This is looking at the thickness of the yarn, not the actually weight of the ball.


Does yarn weight really matter?
In one word yes it does. The weight that you choose is important as it helps you make the correct gauge. You will notice that on most ball bands you will see that some


What does ply mean?
This is the thickness of the yarn.

Eg. 8ply is the thickness and is has 8 strands twisted together to create the yarn.
The weight of yarn will determine the impact of your finished project.


If you live local to Romford, why not come to our Saturday Knit and Natter 7th May 2016, at 10am.
This session is open to all ages.


I hope that this is useful to you.






  • Isobe

    Many thanks for the information which I have been looking for. Clear and comprehensive Will bookmark!

    • You are welcome Isobe

  • Annetta wiĺiams

    I have just downloaded a pattern for a crochet support cushion. The yarn is American bulky. Would two strands of Aran be the equivalent please

  • Sheila

    Thank you for the information… I was getting confused with the details given for yarns… Fingering worsted etc etc

  • diane hedges

    I have had some Aran wool for ages and now thanks to you I can use it. Thank you again.

  • Claudia

    I was looking this kind of information! Very clear to understand! Thank you!