Eyelet sizes are the first thing to sort out before you order. An eyelet has to suit the thickness of your fabric, the cord or tape that will pass through it, and the tool you will use to set it. Numbering can be confusing, though: a "No.2" from one manufacturer may differ from another by a fraction of a millimetre. This guide explains how eyelet sizes are measured, which numbers are used for what, and how to get the right one first time.
How eyelet size is measured
Every metal eyelet has three key measurements:
- Outer diameter – the width of the flange (rim) you see on the right side.
- Inner diameter (hole) – the actual opening the cord, lace or ring passes through.
- Barrel height – the length of the tube, which decides how thick a material the eyelet can grip.
When you see a label like "No.3 – 9.4 x 5 mm", the first figure is the outer diameter and the second is the hole. For cords, always look at the second figure: the hole should be at least 0.5–1 mm larger than the cord so it runs freely.
Round eyelet size chart
Here are the sizes of our PE 0001 domed eyelets and the jobs each number is typically used for:
| Number | Outer x hole | Typical use |
|---|---|---|
| No.17 | 7 x 3.6 mm | shoelaces, corsets, children's clothing |
| No.2 | 8.5 x 4.7 mm | hoodies, drawstrings with 3–4 mm cord |
| No.3 | 9.4 x 5 mm | joggers, sports trousers, sneakers |
| No.4 | 11.5 x 6 mm | jackets, backpacks, cord up to 5 mm |
| No.5 | 15.2 x 7.9 mm | bags, totes, thicker cord |
| No.24–No.26 | 19–24.5 x 9.35–11.5 mm | drawstring bags, decorative openings |
| No.28–No.34 | 25–46 x 13.5–27.7 mm | curtains, banners, covers, rope |
Our PE 0002 flat eyelets follow a similar numbering with an "F" suffix (No.2F, No.3F and so on), with only minor differences in hole size. The PE 0003 oval eyelets are chosen by their outer dimensions and height, as they are mostly used with tapes and belts.
Choosing the number step by step
- Measure the cord or tape. The eyelet hole should be at least 0.5 mm bigger.
- Check the material thickness. Thin fabrics such as jersey or cotton suit smaller eyelets; for canvas and leather choose a taller barrel.
- Think about the load. Where the opening will be pulled hard, a larger size spreads the force over a bigger area.
- Match your tool. The die and hole punch must be made for the same number, otherwise the eyelet will not roll over properly.
- Pick the look. Domed eyelets are rounder and more classic; flat eyelets look cleaner and more modern.
Colour and finish
Beyond size, choose a colour that matches the rest of your hardware – zips, buckles and rings. At Bul-tex you'll find eyelets in gunmetal, gold, silver and black oxide. If your project also uses buckles or rivets, keep them in the same tone for a finished, consistent look.
Frequently asked questions
What eyelet do I need for a 4 mm cord?
Pick an eyelet with a hole of at least 4.7–5 mm, such as No.2 (4.7 mm hole) or No.3 (5 mm hole). If the cord is dense or has an aglet, No.4 with a 6 mm hole is the safer choice.
Are eyelet numbers the same across all brands?
Not exactly. Numbering is a guide and can vary by fractions of a millimetre between makers, so always check the real measurements in millimetres rather than relying on the number alone.
Can I put a large eyelet on thin fabric?
Yes, but reinforce the spot with interfacing or an extra layer of fabric first. Otherwise thin material can tear away around the eyelet when it is under strain.
Browse every size and colour in our eyelets collection and choose the exact number for your project.
