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Watch Lug Width Chart
The one number that decides which strap fits — with the figure for dozens of popular watches, and how to measure yours.
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Lug width is the single measurement that decides which strap fits your watch. It is the gap between the lugs — where the strap sits — measured in millimeters, and it is almost always an even number: 18, 20 and 22mm are the common ones. Buy the wrong width and the strap simply will not fit. This chart lists the lug width for dozens of popular watches, so you can order the right strap without guessing.
Don't see your watch? It takes one minute to measure — skip to how to measure a watch strap. And once you know the number, our best watch straps guides rank the options in every material.
Lug width by model
Widths below are the standard figure for the model as published by the manufacturer. Where a model has multiple case sizes, the common lug width is shown; always double-check your specific reference if you can, because a strap that is even 1mm off will not seat correctly.
Seiko
| Model | Lug width |
|---|---|
| Seiko 5 Sports (SRPD / SKX-successor) | 22mm |
| Seiko SKX007 / SKX009 (discontinued) | 22mm |
| Seiko Prospex Turtle | 22mm |
| Seiko Prospex Samurai | 22mm |
| Seiko 5 Sports GMT (SSK) | 22mm |
| Seiko 5 SNK809 / SNK807 | 18mm |
Orient
| Model | Lug width |
|---|---|
| Orient Kamasu | 22mm |
| Orient Mako II / III | 22mm |
| Orient Ray II | 22mm |
| Orient Bambino | 21mm |
Citizen
| Model | Lug width |
|---|---|
| Citizen Promaster Diver (BN-series) | 20mm |
| Citizen Eco-Drive Garrison / Chandler | 22mm |
| Citizen Eco-Drive Avion | 20mm |
Hamilton, Timex & others
| Model | Lug width |
|---|---|
| Hamilton Khaki Field (38mm) | 20mm |
| Hamilton Khaki Field (42mm) | 20mm |
| Timex Expedition Scout (40mm) | 20mm |
| Timex Weekender (40mm) | 20mm |
| Timex Q GMT (38mm) | 20mm |
| Invicta Pro Diver 8926 (40mm) | 20mm |
| Casio Duro MDV106 | 22mm |
A quick sanity check: most watches use a lug width that is exactly half the case diameter, give or take a millimeter. A 40mm watch is usually 20mm; a 42–44mm watch is usually 22mm. It is a rule of thumb, not a law — but if your measurement lands far from it, measure again.
Why lug width matters more than any other spec
Case diameter gets all the attention, but lug width is the number that actually governs your options. It decides which of the thousands of aftermarket straps will fit, and it is the reason we print it for every watch on this site. A watch with a common 20mm or 22mm lug opens onto an enormous strap market; an odd size like 21mm (the Orient Bambino) narrows your choices considerably.
When the number isn't standard
A few watches don't play by these rules. Integrated-bracelet watches (and some pilot watches like the Citizen Nighthawk) are designed around a fitted bracelet rather than a standard strap. Watches with fixed lug bars — like some field and G-Shock models — can't take a spring-bar strap at all. When in doubt, measure, and if the lugs are fixed or integrated, a standard strap won't fit no matter the width.
Questions
Frequently asked
How do I find my watch's lug width?
What is the most common watch lug width?
Can I put a 22mm strap on a 20mm watch?
Keep reading
Related
Receipts
Sources
- Seiko — product specifications
- Orient Watch USA — model specifications
- Hamilton — Khaki Field specifications
We do not run a testing lab, and we do not pretend to. Every spec above traces to a manufacturer listing or a named standard; where we could not verify something, we say so on the page rather than quietly leaving it out. Read our full method.