How Should a Watch Strap Fit? The Middle-Hole Rule Explained
Which hole is your watch strap using right now?
If you're always fastening it on the very first hole or the very last one, it might be a sign that the strap length isn't ideal for your wrist.
For many traditional watch straps, a good starting point is simple:
Aim for the middle hole.
It gives you adjustment room in both directions and allows the strap to accommodate normal changes in wrist size.
But there's a little more to getting the perfect fit.
1. The Middle-Hole Rule
The middle hole is a useful reference point when choosing strap length.
Ideally, the tang should sit somewhere around the middle of the available adjustment holes, leaving several holes available on either side.
Why?
Because your wrist isn't exactly the same size all day, every day.
Your wrist can change slightly because of:
- Temperature
- Exercise
- Time of day
- Fluid retention
- Normal daily movement
Leather can also relax and soften slightly with wear.
Having adjustment holes available in both directions gives you room to adapt.
The middle hole isn't a law—it's a useful target.
2. Why Do Watch Straps Have Multiple Holes?
Those extra holes aren't there just for decoration.
They allow you to fine-tune the fit.
A strap that's slightly looser in the morning may need a tighter setting later in the day.
In warmer weather, your wrist may expand.
In colder weather, it may become slightly smaller.
A good strap should give you enough adjustment range to accommodate these changes without forcing you to buy a completely different length.
3. Understanding Strap Measurements
Watch strap sizes can look confusing at first.
You may see something like:
75 / 125 mm
This normally refers to the approximate length of the two strap pieces:
75 mm — Buckle Side
The shorter piece carrying the buckle, normally positioned at 12 o'clock.
125 mm — Tail Side
The longer piece with the adjustment holes, normally positioned at 6 o'clock.
Together, these dimensions describe the strap length.
However, manufacturers don't always measure straps in exactly the same way, so it's important to check the individual brand's sizing information.
4. How to Measure Your Wrist
Before choosing a strap length, measure your wrist circumference.
You don't need specialist equipment.
Method 1 — Soft Measuring Tape
Wrap a flexible measuring tape around your wrist where you normally wear your watch.
Keep it:
Snug, but not tight.
Record the measurement in millimetres.
Method 2 — Paper Strip
No measuring tape?
Use a thin strip of paper.
- Wrap it around your wrist.
- Mark where the paper overlaps.
- Lay it flat.
- Measure the length with a ruler.
That's your approximate wrist circumference.
5. HMS Strap Size Guide
As a general HMS reference:
| Wrist Circumference | Recommended Size |
|---|---|
| Under 155 mm | XS / S |
| 155–180 mm | M |
| 180–200 mm | L |
| Over 200 mm | XL |
These ranges are a starting point rather than a universal rule.
The actual fit can also depend on:
- Strap length
- Hole spacing
- Strap thickness
- Watch case size
- Lug-to-lug distance
- How you prefer to wear your watch
Always check the specific strap's sizing information before ordering.
6. Your Watch Size Also Matters
Your wrist measurement isn't the only factor.
The watch itself takes up part of the available space on your wrist.
A large watch with a long lug-to-lug measurement can sit across more of your wrist than a compact dress watch.
This can change how much strap length you actually need.
For example:
Large Pilot / Tool Watch
A larger case can cover more of the wrist, potentially reducing the amount of strap needed around the wrist.
Slim Dress Watch
A smaller, thinner case may leave more of the wrist exposed, potentially requiring slightly more strap length.
If you're between two sizes, consider the watch case and lug-to-lug measurement, not just your wrist circumference.
7. What Does a Properly Fitted Strap Feel Like?
Once the strap is fastened, it should feel secure without squeezing your wrist.
A useful starting point is:
You should be able to slide approximately one finger underneath the strap.
The watch shouldn't move excessively around your wrist, but it shouldn't feel restrictive either.
The tail should also sit neatly through the keepers without an excessive amount of loose material.
A good fit should feel almost unnoticeable.
HMS Tip 💡
Don't obsess over landing on exactly one particular hole.
If your strap fits comfortably on the second, third or fourth hole, that's perfectly fine.
The real goal is:
Secure + Comfortable + Enough adjustment room
The middle hole is simply a useful indication that the strap length is probably in the right range for you.
What If You're Between Two Sizes?
This is where things get more interesting.
If your wrist sits close to the boundary between two strap sizes, consider:
Your watch
Large case → may require less strap length around the wrist.
Small case → may require more.
Your preferred fit
Do you prefer your watch snug?
Or slightly relaxed?
The strap construction
A thick, padded strap can feel different from a thin, flat strap even when both have the same nominal length.
Hole spacing
Two straps with identical total lengths can fit differently if their adjustment holes are positioned differently.
The Final Fit Check
Before deciding that your strap is the wrong size, check four things:
1. Tang position
Ideally around the middle of the adjustment range.
2. Comfort
Secure, but not tight.
3. Finger space
Approximately one finger underneath is a useful starting point.
4. Tail position
The excess strap should sit neatly through the keepers.
If all four look right, you've probably got a good fit.
Conclusion
Choosing the right watch strap isn't simply about matching your watch's lug width.
You need to consider wrist circumference, strap length, hole spacing, watch size and personal preference.
The middle hole is a useful target because it gives you adjustment room in both directions.
But the perfect fit isn't about hitting one specific hole.
It's about finding the point where the strap feels secure, comfortable and natural on your wrist.
Measure your wrist. Check the strap length. Then let your wrist decide.
Recommended Reading
M Size vs L Size: How to Measure Your Wrist
Learn how to measure your wrist accurately and choose the right strap size.
Lug Width 101: The One Measurement You Need Before Buying a New Strap
Understand the difference between lug width and strap length.
Strap Construction 101: What's Really Inside Your Watch Strap?
Discover how the different layers and components of a strap affect its feel and construction.
Parts of a Watch Strap — And Their Names
Learn the names and functions of the eight main parts of a watch strap.
Watch Strap Care Guide
Learn how to keep your leather strap comfortable and in good condition for longer.
Find the Right Fit for Your Watch
The right strap should do more than fit your lugs.
It should fit your wrist.
Explore HMS watch straps in different lengths, widths and leather styles, and find the combination that works for your watch and your wrist.