Apple Watch Series 12 vs. Ultra 4 Buyer's Guide - MacRumors

The Apple Watch Series 12 and Ultra 4, covered in a MacRumors buyer's guide dated September 18, 2026, both use the S11 chip, 4GB of RAM, 64GB of storage, and the new Health Sensing System that measures heart rate every five seconds throughout the day.
The two models share the same everyday health features, including Readiness, Recovery HRV, daytime vitals, improved step tracking, hypertension and sleep apnea notifications, and Sleep Score, so the Ultra's higher price does not add advanced health tracking.
Pricing starts at $399 for the Series 12 and $799 for the Ultra 4; the gap narrows with a titanium Series 12 at $699, and a new ceramic Series 12 option at $899 actually exceeds the Ultra's price despite its smaller size and shorter battery life.
The Series 12 features a rounded design with curved front glass and comes in aluminum, polished titanium, or polished ceramic in 42mm and 46mm sizes, while the Ultra 4 has a rugged 49mm blasted titanium case built for durability, extended battery, and activities like diving and exploration.
Display differences favor the Ultra 4, with a 422-by-514-pixel screen, 1,245 sq mm area, and up to 3,000 nits peak brightness, compared with the Series 12's smaller displays and up to 2,000 nits.
The Ultra 4 adds exclusive Wayfinder, Modular Ultra, and Orienteering faces, an 86-decibel siren, a customizable Action button, dual speakers, and a three-microphone array with beamforming, whereas the Series 12 has a single speaker and single microphone.