An Easy Guide to Button Measurement and Sizing

Millimetres? Inches? Ligne? Button sizes can be pretty confusing! But if you’re a garment designer or a button wholesaler, understanding how to measure a button is super important. That’s why we’ve put together this easy guide to button measurement and sizing.

Here you’ll find the different units used to measure buttons. And some other useful tips for finding exactly the right sized button for your project.

Button Ligne – Millimetres (mm) – Inches

Ligne (from the French for line) is the traditional unit for measuring buttons. In fact it was first used by button manufacturers way back in the 9th century.

It’s still in standard use today. So if you’re using buttons in your work, chances are you’re going to come across it.

To give you an idea of what a ligne means in terms of button size, 40 ligne (40L) is the same as 1 inch. Or 25mm. And 1 ligne (1L) is equivalent to 0.635mm.

They’re certainly not easy conversions to do in your head. So having a button size chart as a reference is a good idea when sizing button.

Button Size Chart

You can use this button size chart to convert ligne to millimetres (mm) to inches. So it’s great for whatever unit of measurement you want to use.

For example, if you want to know how big is 20mm in inches, check the second column (mm) and find 20mm, then you will get the answer: 13/16 inches

Ligne (L)Milimeteres (MM)INCH
button measurement-button size chart

Download this printable button ligne chart (button sizes chart) for accurate measurement.

How to Measure Buttons Sizes

Now we know the units we use to measure buttons. But what is the best method for actually measuring a button? For example, how big is 25mm?

The easiest and most reliable way to measure buttons is with a tool designed precisely for this kind of job. The vernier caliper is a button measuring tool used to measure round and cylindrical objects. Its adjustable jaws hold your button in place so you can get an exact measurement.

If you’re using a round button, the measurement is the diameter of the button. If you’re using a different shaped button, such as an oblong or an oval, the measurement will be the longest edge or diameter.

Most vernier calipers use metric and imperial measurements. Not ligne, unfortunately. So if you’re working in ligne, you’ll need to convert your sizes.

But, a little more helpfully, these tools are available in digital format too. So you can read precise measurements on a screen rather than having to squint at tiny distance markings.

Choosing Buttons? A Few Other Things to Consider

  • Depth as well as button dimensions. The depth of the buttons you choose can be as important as their length. Some buttons are quite fat and you need to consider how this would look on your finished project.

  • Button material. Buttons can have a huge impact on the overall look of a garment. So you need to think carefully about which buttons are right for the job. For instance, rhinestone buttons bring a bit of bling to a garment. While leather buttons give a classic, traditional feel.

  • Standard button sizes. If you’re creating a classic garment, there may be a standard size for the buttons you include. For instance, the average button size for a man’s shirt will have 13L buttons on the collar, 15L on the cuffs and 16L to 20L on the placket.

    Men’s suits usually have a 24L button on the jacket cuff and trouser. And a 32L buttons to fasten the jacket.

  • Buttonhole size. As a general rule, buttonholes should be 3mm bigger than the button diameter.

  • Buttonhole placement. Found an amazing button to go with your garment? But it’s not the size instructed in your pattern? You can still use your button. Just make some simple adjustments to your pattern before you cut it. 

When you have the right tools and the right charts, button measurement becomes a piece of cake. Get in touch if you have any more questions about button sizing. Or check out our catalogue for button inspiration.

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SUNMEI is a specialized manufacturer of acrylic rhinestone and button for over 20 years. We provide a wide selections of acrylic rhinestones and buttons. Visit our product page and find out more styles!