To learn which Apple Watch you have, use its model number:
1. Open the Apple Watch app on your iPhone.
2. Tap the My Watch tab, then tap General > About.
3. Find the Model field. You should see the part number that begins with "M".
4. Tap the Model field. You should see the field update to show a five-digit number that begins with "A". This is your model number.
5. Compare your model number to the ones below.
44mm Display/Case Size - Series 4, 5, 6 & SE
Model numbers:
Series 4 (4th generation) - A1978, A1976, A2008
Series 5 (5th generation) - A2093, A2095, A2157
Series SE (6th generation) - A2352, A2354, A2356
Series 6 (6th generation) - A2292, A2294, A2376
40mm Display/Case Size - Series 4, 5, 6 & SE
Model numbers:
Series 4 (4th generation) - A1977, A1975, A2007
Series 5 (5th generation) - A2092, A2094, A2156
Series SE (6th generation) - A2351, A2353, A2355
Series 6 (6th generation) - A2291, A2293, A2375
42mm Display/Case Size - Series 0, 1, 2 & 3
Model numbers:
Series 0 (1st generation) - A1554
Series 1 (2nd generation) - A1803
Series 2 (2nd generation) - A1758, A1811
Series 3 (3rd generation) - A1859, A1861, A1891, A1892
38mm Display/Case Size - Series 0, 1, 2 & 3
Model numbers:
Series 0 (1st generation) - A1553
Series 1 (2nd generation) - A1802
Series 2 (2nd generation) - A1757, A1816
Series 3 (3rd generation) - A1858, A1860, A1889, A1890