Manufacturer · Fashion & Home Accessories
Snap button sizes are indicated by the diameter of the cap in millimetres, and sometimes in ligne (L), where 1L = 0.635 mm. The most common sizes are around 8–10 mm for baby and children's clothing, 10–12.5 mm for shirts and blouses, 12.5–15 mm for jackets and denim, and 17 mm and above for coats, bags, and decorative accents. Besides the diameter, the stem length is also important and should correspond to the fabric thickness.
How snap button size is measured
The size in the catalogue almost always refers to the visible cap diameter. The socket and stud, which secure the fastening, are standardized for each model and do not always increase proportionally with the cap. Therefore, two snap buttons with the same cap but different models may have different fastening strengths. Some manufacturers also use sizing related to ligne – for example, 24L corresponds to about 15 mm.
When ordering, specify:
- cap diameter in mm;
- model (with ring, with stem, with open teeth);
- stem length or fabric thickness;
- finish and colour.
Snap button sizes: table
| Diameter | ≈ Ligne | Typical Use |
|---|---|---|
| 6–8 mm | ≈ 10–12L | baby clothes, fine lingerie, doll and miniature items |
| 9–10 mm | ≈ 14–16L | bodies, children’s wear, knitted blouses, pajamas |
| 11–12.5 mm | ≈ 18–20L | shirts, dresses, sports tops, pockets |
| 13–15 mm | ≈ 21–24L | jackets, denim, workwear, hoodies |
| 17–20 mm | ≈ 27–32L | winter jackets, coats, bags, backpacks |
| 21–40 mm | ≈ 33–63L | decorative caps, accessories, leather haberdashery |
The table is indicative. The final choice depends on the design and whether the button is functional, decorative, or both.
How to choose size by product type
Baby and children’s clothing
Small snap buttons of 8–10 mm are lightweight, do not weigh down thin knits, and fasten with light force – important for bodysuits that are opened multiple times a day. For knits, snap buttons with open teeth are often used, which pierce the fabric without cutting the threads.
Shirts and blouses
Snap buttons sized 10–12.5 mm replace classic buttons on western shirts, sports shirts, and children’s models. The larger cap attracts attention and is often enamelled, mother-of-pearl, or coloured for effect.
Jackets and denim
Here, the load is greater and the fabric thicker. Sizes 13–15 mm with stronger springs and longer stems are standard. For winter and padded jackets with multiple layers, choose 15–17 mm and check the stem length on a sample.
Bags, backpacks, and leather goods
Caps of 15–20 mm and above provide a good surface for logos and withstand frequent opening. For leather, the stem length is chosen precisely according to thickness, as leather does not shrink like textiles.
Cap diameter and stem length
The two parameters are not directly related: a 12.5 mm button can have a short stem for shirts or a long stem for denim. The stem length is chosen according to the total thickness of materials the button passes through, including interfacing. A stem that is too short will not rivet properly and the button will fall off; too long and it will bend sideways.
- thin fabrics (knitwear, poplin) – short stem;
- medium thickness (double cotton, twill) – standard stem;
- thick fabrics (denim, canvas, leather, padded items) – long stem.
Large snap buttons
Large snap buttons over 20 mm are mainly sought for decorative effect – on coats, caps, bags, cases, and leather accessories. Their cap is larger than the functional part, so the socket and stud are sometimes the same size as on a 15 mm button. This makes the button look massive but fasten with normal force. The wide cap is ideal for embossed logos, engraving, or coloured enamel. Note that large caps are heavier and more visible, so the fabric underneath must be reinforced and the placement carefully marked, as any misalignment is immediately noticeable. Always request a sample and test the die for large models.
Fastening strength
The force required to unfasten the button depends on the spring and socket model, not just the diameter. Baby clothes require light and soft fastening force; jackets and bags need stronger hold to prevent accidental opening. When ordering, mention the product type so the appropriate model can be recommended.
Matching with other metal details
If the product also has eyelets, rivets, or metal buttons, choose sizes in proportion. For example, a jacket with 15 mm snap buttons and eyelets for hood cords usually has smaller eyelets but with the same finish. See eyelets and metal buttons to maintain a consistent look. Available snap button sizes can be found in the snap buttons category.
Common sizing mistakes
- choosing only by cap size without checking stem length;
- too large a button on thin knitwear – weighs down and stretches fabric;
- too small a button on a jacket – hard to fasten with gloves;
- mixing sizes from different manufacturers with different dies.
Custom sizes from Polkom
Polkom is a manufacturer with over 30 years of experience producing snap buttons in sizes from 6 to 40 mm, with various models, finishes, and custom logos. Send us the product type, fabric thickness, and desired size via the contact page – we will propose the suitable model and provide a sample.
