Christmas Trees

1. Take the watch off and look at the back of the case. Apple engraves the case size there, in small text under the sensor — 38, 40, 41, 42, 44, 45, 46 or 49mm.
2. Can’t read it? On the watch, open Settings → General → About. That screen gives you the Model Name and Model Number rather than the size, and Apple’s Identify your Apple Watch page matches the number to a case size.
3. Careful — 42mm means two different watches. Series 1, 2 and 3 came in 38 and 42mm, so on those 42mm is the large one. Series 10 and 11 came in 42 and 46mm, so on those 42mm is the small one. If your watch is a Series 10 or 11, choose the option that says 42mm Series 10/11, not the 42/44/45/46/49mm one.
4. Which leaves three choices: 38/40/41mm, 42mm Series 10/11 on its own, and 42/44/45/46/49mm for every other case — including the 42mm on a Series 1, 2 or 3.

For the length, measure around your wrist: S/M fits 5.1″–7.1″, M/L fits 5.9″–7.9″. If you are between the two, size up — whichever of S/M and M/L the size list on this page offers for your case.

Those are the same ranges Apple uses for its own Sport Band, so if you know which of Apple’s two sizes fits you, pick the same one here.

1. On the watch, open Settings → About watch (older ones say About device) and read the Model number — it starts SM-R. It is usually printed on the back of the case as well.
2. The 20mm ones — what these bands are made for — are the original Galaxy Watch 42mm, the Watch Active and Active 2, the Watch 3 41mm, and the Watch 4, 5, 6 and 7 including their Classic and 5 Pro versions.
3. The 22mm ones are the original Galaxy Watch 46mm, the Watch 3 45mm and the Gear S3. A 20mm band will not fit those.
4. Galaxy Watch 8 and 9 take neither of those. Samsung changed the fitting, so a Series 1–7 band will not go on — they have their own, which is the Series 8 / 9 option above.
5. Watch Ultra: message me before ordering. Its fitting is different again and I would rather check than have you send one back.

Gap Fit is the straight 20mm strap. It fits any 20mm lug, Watch 3 included, and leaves a small gap where it meets a round case.

Snug Fit has shaped ends that sit flush against the case with no gap, but it is cut for the Watch 4, 5, 6 and 7 bodies (Classic and 5 Pro included) — it does not fit the Watch 3.

Series 8 / 9 is the same kind of band again, cut for the newer fitting. It is not interchangeable with either of the other two.

1. On the watch, swipe down and tap Settings, then System → About. The generation and the case size are both on that screen.
2. Pixel Watch 1 and 2 were only ever made in 41mm, so if you have either of those there is nothing to work out — the 41mm band is the one.
3. Pixel Watch 3, 4 and 5 each come in 41mm and 45mm. Check the About screen rather than guessing: 4mm is very hard to judge by eye.

The 41mm and 45mm bands here are different parts — a 45mm band will not go on a 41mm watch.

The bands on sale are listed for Watch 1, 2 and 3 in 41mm and Watch 3 and 4 in 45mm. If you have a Watch 4 in 41mm, or a Watch 5, message first and we will confirm the fit before you order rather than guess it.

1. Turn the watch over and look at where the band meets the case. If you can see a metal pin bridging two little lugs, with a tiny lever you press inward along the pin, you have a Versa, Versa 2, Versa Lite or Versa SE.
2. If there is no pin and no lugs — the band end slides straight into a slot in the case and is released by a flat button you slide toward the band — you have a Versa 3, Versa 4, Sense or Sense 2.
3. That one look is more reliable than the model name, because the two generations look almost identical from the front.

These two groups genuinely do not interchange. Fitbit changed the fitting between them, so a Versa 2 band will not attach to a Versa 3 and neither one takes an ordinary watch strap.