Can a watch have an odd lug width like 21 mm?
Yes, and roughly one watch in six does. An odd size is a real measurement, not a rounding error.
6,458 of 39,739 measured watches take an odd lug width. Measured 2026-08-27.
The odd sizes that actually exist
How many watches in the database take each one.
- 21 mm2,462
- 19 mm1,631
- 23 mm563
- 17 mm526
- 15 mm459
Where you meet them
The brands with the most odd-width references. Longines alone accounts for 24% of them.
Do not round it off
A 20 mm band in a 21 mm gap leaves a millimetre of daylight on each side, the band shifts under the lugs and the spring bar takes the strain. Going up instead of down is worse: a 22 mm band has to be forced, and forcing it marks the inside of the lugs.
Odd sizes are made. If a reference measures 21 mm, that is the size to order. Half sizes are a different story: those are almost always a measuring error.
Check your own reference
Family averages are the reason people order the wrong size. Your reference has its own measured number, and it is in the database.
Search your referenceOther questions
- Does lug width change within the same watch family?67.7% of watch families use more than one lug width. Knowing the family is not enough.67.7%
- What is the most common lug width?20 mm, on 38.8% of measured watches. What the rest of the distribution looks like.20 mm
- Why will no strap fit my watch?6.1% of watches have no lug width at all. Here is what to do instead.2,632
- What length watch strap do I need?Ready-made straps come in one length only. Whether that length reaches you is a different question.75/115 mm