The modern buttons as a fastening system we know today were introduced in the 13th century, far before the invention of the standardized metric system in the 1700s.

How did garment makers back then measure button sizes? The answer is button ligne, which is the topic of our discussion today. Button ligne as a measurement system for button size is still retained today. So understanding it will be very important for garment manufacturers and merchandisers.

Let us begin by discussing a brief history of the ligne itself.

What is Button Ligne
Ligne is a French word meaning “line”, and button ligne as a measurement system for button size was first used by German button manufacturers in the 9th century, although it finally became the standard measurement much later by the 18th century.

Ligne is expressed as “L”. If you ever encounter 10L in a button, that means 10 ligne, an equal of 1/4 inch in diameter.

How to Calculate Button Ligne
While measuring ligne unit might not be familiar to the most of us, we are all familiar with the modern metric system in meter or inch. To calculate button ligne, all we need to do is to convert it into millimeters or inches.

As the standard, 40 ligne or 40L equals 1 inch or 25 milimiters. So 1L equals 0.635mm. To calculate button size in ligne, simply divide the diameter of the button (in millimeters) by 0.635.

Button Ligne= button diameter (mm)/0.635

For example, if your button diameter is 18mm, the calculation becomes:
Ligne=18/0.635
=28.34

Rounded down, the button ligne is 28L

The table below lists the various common conversion between ligne and inch/millimeter.

Standard Button Size Measurement Chart

Ligne MM INCH
12 7.5 5/16
13 8 5/16
14 9 11/32
15 9.5 3/8
16 10 13/32
17 10.5 7/16
18 11.5 15/32
20 12.5 1/2
22 14 9/16
24 15 5/8
26 16 21/32
28 18 23/32
30 19 3/4
32 20 13/16
34 21.5 27/32
36 23 7/8
38 24 15/16
40 25 1
42 26 1-1/25
44 28 1-3/32
45 30 1-3/16
48 30 1-3/16
54 34 1-5/16
60 38 1-1/2
64 40 1-9/16

Remarks: Please refer to the image below for the correct measurement of button/buckle diameter.

End Words
While button ligne might sound complicated at first, calculating it is actually fairly simple. Understanding the ligne measurement system is very important in the garment industry, as the wrong button size can lead to faulty products.

By following the calculation we have shared above, you can easily convert any button diameter from inch or millimeter into ligne.