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How to Measure a Curling Iron and Choose the Right Size for You

Last Updated on 13th September 2021 by Chauncey Morgan

how to measure curling iron

Have you ever found yourself wondering which size curling iron would be best for your hair? I know that the size is usually written on the packaging of the curling iron, but what if it is not? Would you know how to measure your curling iron, or would you find yourself in a bit of a dilemma?

One of the most important things you should know about curling irons is their size. This is crucial as having the wrong size curling iron can actually lead to more difficulties when styling your hair. Your curls will be far from what you expect if the curling iron is either too big or too small.

If you want to style your hair just the way you like it and without any difficulties along the way, you will need to check the size of your curling iron and make sure that it is the right size for your hair length, texture, or style. In this guide, I will tell you all you need to know on how to measure a curling iron including why you should know this information.

So if this is something that you are interested in learning, I suggest you pay close attention as I get right to the explanation!

How to Measure Curling Iron Size

When it comes to measuring the size of your curling iron, you will want to focus on measuring the barrel length and diameter. The barrel length and diameter can help you achieve different types of curls, but at the same time, different barrel sizes will be suitable for different types of hair.

First, let’s talk a bit about how to measure the length and diameter of the barrel and then I’ll go into the functionality of the barrel depending on the length and diameter.

How to Measure Barrel Length

Curling irons can come in different lengths, but they most often are around 12 inches. Those 12 inches include the barrel and the handle, not the cord.

measuring curling iron

If you want to measure the length of the curling iron, you can do that easily using a measuring tape. Place the beginning of the measuring tape at the tip of the barrel and stretch it right to the end of the handle. Depending on your specific type of measuring tape, you will get the length in centimeters or inches.

How to Measure Barrel Diameter

When it comes to the barrel of the curling iron, what you essentially need to measure is not the length of it but the diameter. You can do that by using a measuring tape, but make sure that your curling iron is off when measuring it – if it is on, there is a good chance you will burn your hands in the process.

I will try to keep this as simple as possible, just in case you are not a math person. The simplest way to measure the diameter of the barrel is by wrapping the measuring tape around it. When you get a number for the circumference, divide it by Pi (which is 3.14), and you will get the diameter of your curling iron.

The usual curling iron sizes start at 3/8 inches and go up to 2 inches.

Curling Iron Size Guide

Here are the different lengths you can expect to come across and what hair types and curl types they are recommended for:

Short Hair

The best curling iron barrel size for short hair is 3/8 inch. With this barrel size, you can achieve perfect tight curls.

I do not recommend this barrel size for thicker or longer hair,mainly because it will take a lot of time to style your entire head of hair. Using a curling iron with even a slighly larger barrel will save you a lot of time and effort.

Medium-Length Hair

The best curling iron barrel sizes for hair that is shoulder length are: 1/2 inch, which is suitable for tight spiral curls; 5/8 inch, which is best for voluminous curls; and 3/4 inch, which can help you achieve the evergreen vintage curls.

You can use any of these barrel sizes on shorter hair as well, but the results might not be as good as you expect them to be. With these barrel sizes, you might not be able to wrap short hair nicely and that might lead to curls that look a bit worn out.

On the other hand, you can use these barrel sizes on longer hair, but again, it will take a lot of time to style all your hair. If possible, you should look into larger barrel sizes for thicker and longer hair, but if that is not an option, these barrel sizes will work as well.

Curling Iron Size Guide

All Hair Lengths

Even though these barrel sizes are often said to be suitable for all hair lengths and types, I recommend that you use the 1-inch, 1-1/4 inch, and 1-1/2 inch barrels on medium to long hair. The barrel size is suitable for several types of curls, but it is best for loose, beachy waves.

That being said, I recommend the 1-3/4 inch and 2-inch barrels for longer hair and hair that is thicker. The large diameter of the barrel will help you style your hair quickly and nicely without having to divide it into many sections. These barrel sizes can be used for other types of hair, but the results will not be that great.

FAQs on Curling Iron Sizes

Before I wrap this guide up, I would also like to mention the most frequently asked question regarding this topic. Here it is:

What is the standard curling iron size?

As a standard curling iron size, I would say the 1-inch curling iron just because it can be used on all hair lengths and for all types of curls. Anything smaller would be more suitable for shorter hair only, while anything larger would be better for longer hair only.

Now You Can Get the Right Size Curling Iron!

I have come to the end of this curling iron size and measurement guide. I hope that everything I pointed out above will help you decide which size curling iron you need and how to check for the size of it before you purchase it. Let me know if you tried measuring your curling iron using this guide. I would love to know how it all went!

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