Choosing the right button isn't just about aesthetics — it's about function, fit, and finish. Whether you're a fashion designer, a tailor, or a passionate home sewer, understanding button diameter and shank types is essential to achieving a polished, professional result. This guide breaks it all down with a complete reference chart.
Why Button Size Matters
A button that's too large overwhelms a delicate blouse; one that's too small won't hold a heavy coat closed. The diameter of a button must be proportional to the fabric weight, the buttonhole size, and the overall garment design. Getting this right is the difference between a garment that looks handmade and one that looks hand-crafted.
Understanding Button Measurement: Ligne (L)
Buttons are traditionally measured in ligne (abbreviated as L or lin), a unit originating from French tailoring. One ligne equals approximately 0.635 mm.
Button Diameter Reference Chart
| Ligne (L) | Diameter (mm) | Diameter (inches) | Recommended Use |
|---|---|---|---|
| 14L | 9 mm | ⅜" | Blouses, lightweight shirts |
| 16L | 10 mm | ⅜" | Dress shirts, children's wear |
| 18L | 11.5 mm | ½" | Shirts, light jackets |
| 20L | 12.5 mm | ½" | Blouses, cardigans |
| 24L | 15 mm | ⅝" | Dresses, skirts, trousers |
| 28L | 18 mm | ¾" | Jackets, blazers |
| 32L | 20 mm | ¾" | Coats, outerwear |
| 36L | 23 mm | ⅞" | Heavy coats, decorative use |
| 40L | 25 mm | 1" | Statement coats, accessories |
| 44L | 28 mm | 1⅛" | Bags, belts, decorative accents |
| 54L | 34 mm | 1⅜" | Decorative, statement pieces |
| 60L | 38 mm | 1½" | Bags, home décor, fashion art |
Shank Types Explained
The shank is the mechanism on the back of a button that attaches it to fabric. Choosing the right shank type affects how the button sits, how it functions, and how long it lasts.
1. Sew-Through (Flat) Buttons
These have 2 or 4 holes on the face and are sewn directly through the fabric. They lie flat and are ideal for lightweight to medium-weight fabrics. Common on dress shirts, blouses, and casual wear.
- Best for: Shirts, blouses, children's clothing
- Fabric weight: Light to medium
- Tip: Create a thread shank when sewing onto thicker fabrics to allow the buttonhole layer to sit smoothly.
2. Metal Shank Buttons
A metal loop or post is cast or welded to the back of the button. The button face can be solid, domed, or decorative. Metal shanks are the hallmark of premium tailoring and outerwear.
- Best for: Blazers, coats, denim, leather goods, bags
- Fabric weight: Medium to heavy
- Shank height: Typically 3–6 mm; choose taller shanks for thicker fabrics
- Tip: Match shank metal finish (gold, silver, antique brass) to other hardware on the garment for a cohesive look.
3. Self-Shank (Tunnel Shank) Buttons
The shank is molded from the same material as the button body — common in plastic and horn buttons. Provides a clean, integrated look.
- Best for: Knitwear, casual jackets, trousers
- Fabric weight: Light to medium-heavy
4. Snap Shank / Prong Shank
Used with tack buttons and jeans buttons, these are attached by a prong that pierces the fabric and locks into a back plate — no sewing required.
- Best for: Denim, workwear, bags
- Fabric weight: Heavy
Shank Height vs. Fabric Thickness
A common mistake is ignoring shank height relative to fabric bulk. Here's a quick guide:
| Fabric Type | Recommended Shank Height |
|---|---|
| Silk, chiffon, lawn | 1–2 mm (thread shank or minimal) |
| Cotton, linen, light wool | 2–3 mm |
| Medium wool, denim | 3–4 mm |
| Heavy wool, canvas, leather | 5–6 mm |
| Quilted or padded outerwear | 6 mm+ |
Quick Selection Guide
Still unsure? Use this decision tree:
- Identify your fabric weight → determines shank height and button size range
- Determine the garment type → shirt, jacket, coat, bag?
- Choose the aesthetic → functional, decorative, or both?
- Match the finish → metal tone, color, and texture should complement the fabric
- Check buttonhole size → buttonhole length = button diameter + button thickness + 3 mm ease
Final Thoughts
The right button elevates a garment from ordinary to exceptional. With this chart as your reference, you'll be able to select the perfect diameter and shank type for every project — whether you're finishing a bespoke coat or sourcing hardware for a full production run.
Browse our full collection of metal shank buttons in sizes from 14L to 60L, available in gold, silver, antique brass, and gunmetal finishes — crafted for designers who refuse to compromise on detail.
