The Apple Watch Series 9 features a 41mm midnight aluminum case with matching midnight sport band in S/M size, designed for wrists 130-200mm. Powered by the advanced S9 SiP with 64-bit dual-core processor and 4-core Neural Engine, it introduces innovative Double Tap gesture control allowing interaction without touching the screen. The always-on Retina LTPO OLED display delivers exceptional visibility with up to 2000 nits maximum brightness and edge-to-edge coverage at 326 pixels per inch.

Health and wellness features include electrical and third-generation optical heart sensors, temperature sensing, ECG app, cycle tracking with retrospective ovulation estimates, sleep tracking with sleep stages, and irregular rhythm notifications. Advanced workout capabilities cover running with custom intervals and race routes, cycling with power zones and cadence tracking, swimming with automatic stroke detection, hiking with topographic maps and backtrack GPS, plus over 30 additional workout types.

Safety features include Emergency SOS, international emergency calling, crash detection, and fall detection. The watch offers IP6X dust resistance and 50-meter water resistance suitable for swimming. Connectivity includes L1 GPS with GNSS, Galileo, and BeiDou positioning, Wi-Fi 4, Bluetooth 5.3, and second-generation Ultra Wideband chip for precision finding. Battery life delivers up to 18 hours of all-day use or up to 36 hours in Low Power Mode, with fast charging reaching 80% in approximately 45 minutes. Includes Apple Watch Magnetic Fast Charger to USB-C Cable. Requires iPhone Xs or later with iOS 17 or later. Note: Blood oxygen measurement is not available on units with part numbers ending in LW/A sold in the United States beginning January 18, 2024.