A great strap starts with the right fit. Use the chart below to match your Apple Watch case to the right strap size, then measure your wrist and pick your style.
Apple Watch strap compatibility chart
Find your case size (it's engraved on the back of your watch or listed under Settings > General > About), then choose the matching strap group.
Your case size
Choose this strap size
38mm, 40mm, 41mm, 42mm
38mm/40mm/41mm/42mm
44mm, 45mm, 46mm, 49mm
44mm/45mm/46mm/49mm
Straps within the same group fit each other's case sizes, so a strap bought for an older watch will usually carry over to a newer model in the same group. That includes the 46mm Series 10 and the 49mm Apple Watch Ultra in the larger group.
Measure your wrist
Wrap a soft, non-stretch tape measure snugly around your wrist just above the wrist bone and note the measurement. If your tape only shows inches, multiply by 25.4 to get millimetres (a 7-inch wrist is about 178mm). A snug measurement matters most for stretch styles like the Braided Solo Loop, which have no clasp to adjust.
Shop by style
Braided Solo Loop Soft, stretchy braided yarn that slips straight over your hand. No clasp, so pick the snuggest size for your wrist. Shop Braided Solo Loop straps →
Milanese Loop Stainless steel mesh with a magnetic wraparound fit that adjusts to almost any wrist. Perfect for dressing your watch up. Shop Milanese Loop straps →
Quick band sizing reference
Sport Band: S/M or M/L, adjustable with pin holes.
Sport Loop, Milanese Loop, Link Bracelet: one adjustable size per case group.
Solo Loop & Braided Solo Loop: multiple fixed sizes, so measure carefully.
Classic & Modern Buckle: S/M/L sizes.
Wrapping up
Match your case size to the right group, measure your wrist, and choose a style that suits you. A well-fitted strap is more comfortable, keeps sensors like the heart rate monitor accurate, and simply looks better.
