Definitions

• Lug Width: The distance between the inner sides of the lugs (the metal parts that hold the strap). It’s measured in millimeters (e.g., 18mm, 20mm). A watch with a lug width of 20mm will require a strap labeled as a 20mm strap.
• Buckle Width: The inner width of the buckle, or the width of the strap where it attaches to the buckle. It can also refer to the width of the longer strap at the adjustment holes. Many straps taper - for example, a strap with a 20mm lug width would commonly taper to 18mm at the buckle. In this case, the strap would be labeled as 20/18mm.
• Short Side Length: The length of the shorter strap (typically with the buckle attached).
• Long Side Length: The length of the longer strap (the piece with the adjustment holes).
• First Hole from Lug End: The distance from the lug end of the strap to the first adjustment hole. This measurement affects how well the strap fits smaller wrists.
• Last Hole from Lug End: The distance from the lug end of the strap to the last adjustment hole. This determines whether the strap will fit larger wrists.

Measuring your watch’s lug width is an essential step when selecting a strap or bracelet. The lug width is the distance between the inner sides of the two lugs on your watch case. Here’s how you can measure it accurately:

Using Calipers (Recommended for Accuracy):

1. Open the calipers and gently place the tips inside the lugs of your watch.
2. Adjust the calipers so they touch both inner sides of the lugs without applying pressure.
3. Read the measurement displayed on the calipers. Ensure you’re reading the correct (outer) measurement, as the calipers are already positioned between the lugs. This is your lug width in millimeters.

Using a Ruler (Simpler Method):

1. Place the ruler flat against the back of your watch.
2. Align the zero mark of the ruler with the inner edge of one lug.
3. Measure the distance to the inner edge of the opposite lug. Ensure your ruler is straight and level for an accurate reading.

How to measure buckle width

If you plan to use your original buckle or deployant clasp, you’ll need to know the buckle width. Buckles are measured from the inside, just like lugs. Most straps taper, so the buckle width is often smaller than the lug width. For example, a 20mm strap may taper to 18mm at the buckle. This strap would be labeled as 20/18mm.

Using both Measurements to Find the Correct Strap

Once you know your watch’s lug width and buckle width, you’re ready to choose the right strap. For example: if your lug width is 19mm and your buckle width is 16mm, look for a strap labeled as 19/16mm.

Quick Tip: Use Existing Straps

If you already have a strap that fits your watch perfectly, check the back of the strap. Many straps have the lug width (e.g. 20/18) stamped on them for easy reference.

Ready to change your strap?

Although many watch straps feature quick-release spring bars for easy installation, you may need tools to install a new strap or remove your current one. For additional tips on protecting your watch from scratches and a step-by-step guide on changing straps, check out our comprehensive guide on how to change a watch strap.