What size watch strap do I need?

Two numbers, and they come from two different places. The width is decided by your watch: it is the lug width, and it is in the database. The length is decided by your wrist, and ready-made straps come in one length only.

20mm

the lug width on 36.4% of 41,485 measured watches. Measured 2026-10-24.

Lug widths of watches, size by size

Share of every measured watch in the database, by lug width, with the brands where that size is most common. Open a size for every reference that takes it.

Lug width	Watches measured	Share of watches	Most common in
20 mm	15,081	36.4%	Rolex, Omega, TAG Heuer
22 mm	6,971	16.8%	Breitling, IWC, Oris
18 mm	3,965	9.6%	Breitling, Longines, Omega
16 mm	3,009	7.3%	Rolex, Breitling, Omega
21 mm	2,956	7.1%	Longines, Oris, Rolex
24 mm	2,192	5.3%	Panerai, Breitling, Oris
19 mm	1,919	4.6%	Omega, Longines, IWC
14 mm	1,419	3.4%	Rolex, Breitling, Oris
23 mm	655	1.6%	Blancpain, Oris, Zenith
26 mm	582	1.4%	Panerai, Oris, Breitling
15 mm	569	1.4%	Longines, Tissot, Certina
17 mm	569	1.4%	Longines, Oris, Rolex
13 mm	487	1.2%	Longines, Omega, Rolex
12 mm	317	0.8%	Longines, Tissot, Mido

2,640 watches in the database, 5.7%, have no lug width at all: the bracelet is integrated into the case and no standard strap fits. If yours is one of them, the chart cannot help you, and a strap has to be made for the watch.

Which size does my watch take?

The reference decides, not the brand and not the family. Of the 698 watch families measured, 70.3% use more than one lug width across their references, so “a Submariner takes 20” is true for some Submariners and wrong for others.

The three lug widths people search for most, read from the record:

21 mmRolex 126610LN · 41 mm case
20 mmOmega 310.30.42.50.01.001 · 42 mm case
20 mmSwatch SO33N100 · 42 mm case

The same two seconds answer any other reference.

Search your reference

How long should the watch strap be?

One length. Ready-made straps are cut 75 mm on the buckle side and 115 mm on the tail, whatever the watch and whatever the wrist. There is no size chart for length because there is no choice: there is a yes or a no, and it depends on which hole you close on today.

The 7 holes on a standard strap run from 55 mm after the lug to 20 mm before the tip, measured at our bench. Enter your wrist and your watch and the answer is exact: will a standard strap close on you?

A strap that closes on the last hole, or the first, is not the wrong chart. It is the wrong length, and the only fix is a strap cut to your wrist.

Lug width is not the case diameter

A 40 mm case does not take a 40 mm strap, and there is no fixed ratio between the two. Cases of the same diameter take different widths. The number you need is the gap between the lugs, read in whole millimetres: how to measure it.

Odd lug widths are real

18.2% of measured watches take an odd width: 21, 19, 23, 17 or 15 mm. If you read 21, the answer is 21, not “probably 20”. Why odd sizes exist.

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.