Watch Strap Size Guide - Every Brand, Every Size
Buying a new watch strap should be exciting, not confusing. But if you've ever stared at a product page wondering "do I need 20mm or 22mm?"… yeah, we get it. We've been there too.
This guide covers every major watch brand and their most common lug widths, plus how to measure yours at home in about 30 seconds. No guesswork, no returns, no dramas.
What Is "Watch Strap Size" and Why Does It Matter?
When we talk about watch strap size, we're talking about the lug width, the distance in millimetres between the two lugs (those little arms that stick out from the top and bottom of your watch case). This measurement determines which straps will fit your watch.
Get it wrong, and your strap either won't fit at all or it'll look awkward with gaps on either side. Get it right, and it slides in perfectly whether you're fitting a NATO strap, a leather NATO, or a two-piece strap.
The most common sizes are 18mm, 20mm, 22mm, and 24mm. Some watches use odd sizes like 19mm or 21mm, but they're the exception rather than the rule.
How to Measure Your Watch Lug Width
You've got two easy options here:
Option 1: Use a Ruler or Caliper (Most Accurate)
- Remove your current strap if you can (or just work around it)
- Measure the gap between the inner edges of the two lugs, that's the space where the spring bar sits
- Use millimetres, you're looking for a whole number like 18, 20, 22, or 24
- If you get something like 19.8mm, round to 20mm. If you get 21.5mm, it's probably a 22mm watch
A digital calliper from Bunnings gives you the most precise reading, but honestly, a small ruler works fine for most people.
Option 2: Measure Your Current Strap
If you've already got a strap that fits, just measure its width at the end where it attaches to the watch. That's your lug width. Dead simple.
Option 3: Check the Table Below
Look up your watch model in our brand-by-brand guide. We've done the homework, so you don't have to.
Watch Strap Size by Brand - The Complete Table
Here's the bit you actually came for. We've compiled lug widths for the most popular watch models across every major brand. Bookmark this page you'll probably need it again.
Note: Some brands use different lug widths across their range. Always double-check your specific model if you're unsure.
Seiko Strap Size
| Model / Collection | Lug Width |
|---|---|
| Seiko 5 (SNK series, e.g. SNK809) | 18mm |
| Seiko 5 Sports (SRPD series) | 22mm |
| Seiko Presage (most models) | 20mm |
| Seiko SKX007 / SKX009 | 22mm |
| Seiko Prospex "Turtle" (SRP series) | 22mm |
| Seiko Prospex "Samurai" | 22mm |
| Seiko Prospex "Mini Turtle" | 20mm |
| Seiko Cocktail Time | 20mm |
| Seiko Alpinist (SPB series) | 20mm |
Seiko is one of the most popular brands we sell straps for. The classic SKX007 takes a 22mm strap, and it looks absolutely mint on a NATO strap. The older Seiko 5 SNK models are 18mm, don't mix them up with the newer 5 Sports range, which are 22mm.
Citizen Strap Size
| Model / Collection | Lug Width |
|---|---|
| Citizen Eco-Drive Promaster Diver (BN0150) | 20mm |
| Citizen Eco-Drive Promaster Diver (BN0151) | 20mm |
| Citizen Nighthawk | 22mm |
| Citizen Promaster Tough | 22mm |
| Citizen Chandler | 22mm |
| Citizen Eco-Drive Corso | 20mm |
| Citizen Tsuki-yomi (AT series) | 22mm |
Citizen's Eco-Drive divers are a ripper of a watch at the price, and they look great on a rubber or silicone strap for the beach.
Casio Strap Size
| Model / Collection | Lug Width |
|---|---|
| Casio G-Shock DW-5600 | 16mm (proprietary) |
| Casio G-Shock GA-2100 "CasiOak" | 24mm (proprietary adapter available) |
| Casio MDV-106 "Duro" | 22mm |
| Casio A168 (vintage digital) | 18mm |
| Casio F-91W | 18mm (resin, hard to swap) |
| Casio Edifice (most models) | 22mm |
Quick heads up: most G-Shocks use proprietary fittings, so standard straps won't work without adapters. The Casio Duro (MDV-106), though? That's a 22mm standard lug width and an absolute weapon on a NATO. Best $80 you'll spend.
Orient Strap Size
| Model / Collection | Lug Width |
|---|---|
| Orient Bambino | 22mm |
| Orient Kamasu | 22mm |
| Orient Mako II | 22mm |
| Orient Ray II | 22mm |
| Orient Tristar | 18mm or 20mm (varies) |
Orient keeps it simple, 22mm across most of their popular models. The Bambino on a leather NATO is one of the best-looking combos going around.
Tissot Strap Size
| Model / Collection | Lug Width |
|---|---|
| Tissot PRX (40mm) | 12mm (integrated) |
| Tissot Seastar 1000 | 22mm |
| Tissot Gentleman | 21mm |
| Tissot Le Locle | 19mm |
| Tissot Visodate | 20mm |
| Tissot Chemin des Tourelles | 21mm |
Tissot can be a bit tricky with their odd sizes (19mm, 21mm). In most cases, going one millimetre up works fine; a 20mm strap on a 19mm watch will squeeze in and look great. For the PRX, it's an integrated bracelet, so aftermarket straps need a specific adapter.
Hamilton Strap Size
| Model / Collection | Lug Width |
|---|---|
| Hamilton Khaki Field Mechanical | 20mm |
| Hamilton Khaki Field Auto (38mm) | 20mm |
| Hamilton Khaki Field Auto (42mm) | 22mm |
| Hamilton Khaki Aviation Pilot | 22mm |
| Hamilton Jazzmaster | 20mm or 22mm (varies) |
| Hamilton Khaki Navy Scuba | 20mm |
The Khaki Field is practically made for NATO straps. It's a military-inspired watch on a military-inspired strap. Chef's kiss.
Tag Heuer Strap Size
| Model / Collection | Lug Width |
|---|---|
| Tag Heuer Carrera (most) | 22mm |
| Tag Heuer Aquaracer | 20mm or 21mm |
| Tag Heuer Formula 1 | 20mm |
| Tag Heuer Monaco | 22mm |
Omega Strap Size
| Model / Collection | Lug Width |
|---|---|
| Omega Speedmaster Professional (Moonwatch) | 20mm |
| Omega Seamaster 300M | 20mm |
| Omega Seamaster Planet Ocean | 22mm |
| Omega Aqua Terra | 20mm |
| Omega Railmaster | 20mm |
Fun fact: James Bond wore an Omega Seamaster on a NATO strap in Spectre and No Time to Die. If it's good enough for 007, it's good enough for your weekend BBQ.
Tudor Strap Size
| Model / Collection | Lug Width |
|---|---|
| Tudor Black Bay 58 | 20mm |
| Tudor Black Bay (41mm) | 22mm |
| Tudor Black Bay GMT | 22mm |
| Tudor Pelagos | 22mm (proprietary) |
| Tudor Ranger | 20mm |
Tudor actually sells their Black Bay on a fabric NATO from the factory; they know what's up.
Apple Watch Strap Size
| Model | Strap Size |
|---|---|
| Apple Watch 38mm / 40mm / 41mm | Proprietary (use Apple Watch adapter) |
| Apple Watch 42mm / 44mm / 45mm / 49mm (Ultra) | Proprietary (use Apple Watch adapter) |
Apple Watches use a proprietary connector, not standard spring bars. You'll need an adapter to use regular straps. With an adapter, the smaller models take roughly 20mm straps and the larger ones take 22-24mm.
Samsung Galaxy Watch Strap Size
| Model | Lug Width |
|---|---|
| Galaxy Watch 4 / 5 / 6 (40mm) | 20mm |
| Galaxy Watch 4 / 5 / 6 (44mm) | 20mm |
| Galaxy Watch 4 Classic (42mm) | 20mm |
| Galaxy Watch 4 Classic (46mm) | 22mm |
| Galaxy Watch 5 Pro | 20mm |
| Galaxy Watch Ultra | 22mm |
Good news, Samsung uses standard quick-release spring bars, so any regular 20mm or 22mm strap will fit. A silicone strap is great for workouts.
Garmin Strap Size
| Model | Lug Width |
|---|---|
| Garmin Fenix 5S / 6S / 7S | 20mm |
| Garmin Fenix 5 / 6 / 7 | 22mm |
| Garmin Fenix 5X / 6X / 7X | 26mm |
| Garmin Forerunner 245 / 265 | 22mm (proprietary quick-fit) |
| Garmin Forerunner 945 / 955 / 965 | 22mm (proprietary quick-fit) |
| Garmin Venu 2 / 3 | 22mm |
| Garmin Instinct (all models) | 22mm |
Garmin uses a proprietary "Quick Fit" connector on most models. Standard straps won't click in directly, but some models accept standard spring bars if you remove the Quick Fit mechanism. Check your specific model.
Quick Reference: Size at a Glance
| Lug Width | Common Watches |
|---|---|
| 18mm | Seiko SNK series, Casio vintage digitals, smaller vintage watches |
| 20mm | Seiko Presage, Omega Speedmaster, Omega Seamaster 300M, Tudor BB58, Hamilton Khaki Field, Samsung Galaxy Watch, Garmin Fenix S-series |
| 22mm | Seiko SKX/5 Sports, Orient Bambino/Mako/Ray, Casio Duro, Hamilton Khaki 42mm, Tudor Black Bay, Citizen Nighthawk, Samsung Galaxy Watch Classic 46mm |
| 24mm | Panerai, Breitling Navitimer, larger pilot watches |
What If My Watch Is Between Sizes?
If your watch measures at an odd width like 19mm or 21mm, here's the deal:
- 19mm lug width: A 20mm strap will work. It'll be a snug fit but it'll look fine and stay secure. NATO straps are especially forgiving since the nylon compresses slightly.
- 21mm lug width: Go with 22mm. Same logic, slightly loose is better than slightly too narrow, and it'll barely be noticeable on the wrist.
- General rule: If you're between sizes, round up. A strap that's 1mm too wide is better than 1mm too narrow.
Still Not Sure? We're Here to Help
If you can't find your watch in the tables above, just drop us a message with your watch brand and model number. We'll sort you out, that's what we're here for.
Once you know your size, check out our full range:
- NATO Straps - the classic, from $8
- Leather NATO Straps - dress it up
- Silicone & Rubber Straps - built for the water
- Two-Piece Straps - traditional style
Free shipping on all orders over $60, and we ship from right here in Australia.
Frequently Asked Questions
What size watch strap do I need?
Measure the distance between the inner edges of your watch lugs in millimetres. The most common sizes are 18mm, 20mm, 22mm, and 24mm. You can also check our brand-by-brand table above to find your specific model.
Are watch strap sizes universal?
Standard lug widths (18mm, 20mm, 22mm, 24mm) are universal. Any strap in the right width will fit any watch with standard spring bars. However, some watches (Apple Watch, many Garmin models, some G-Shocks) use proprietary connectors.
What size strap does a Seiko SKX007 take?
The Seiko SKX007 takes a 22mm strap. It's one of the most popular watches to put on a NATO strap.
Can I put a 20mm strap on a 22mm watch?
Technically, you can, but it'll leave visible gaps on either side and won't look great. We'd recommend sticking to the correct size. If your watch is 21mm, a 22mm strap is fine, but a 2mm difference is too much.
What size strap does an Omega Speedmaster take?
The Omega Speedmaster Professional (Moonwatch) takes a 20mm strap.
Do NATO straps come in different sizes?
Yes! NATO straps come in 18mm, 20mm, 22mm, and 24mm widths. The length is standard and fits most wrist sizes. Check out our full NATO strap collection.
Posted on 08 December 2025 by Brad Farleigh