Apple Watch SE vs. Apple Watch Series 9: Which is best for you?

One has tons of features, but the other might be all you need

When shopping for an Apple Watch, you have a choice between the flagship Apple Watch Series 9, the rugged Apple Watch Ultra 2 and the entry-level Apple Watch SE. The Ultra 2 is great for athletes, but most people will probably go with the Series 9 or SE. Which one should you choose?

The BestReviews Testing Lab tested both the Series 9 and the current second-generation Apple Watch SE, going over their features, their differences and what they’re each good at. We think the Apple Watch Series 9 is the best Apple Watch model overall, with the fastest performance and the most high-end features. But the Apple Watch SE is no slouch when it comes to everyday smartwatch use, and it’s the best Apple Watch model for the buck.

Apple Watch specs

The Apple Watch Series 9 and SE have a lot of features in common, but they differ in some key areas. For instance, the Series 9 has a faster system, more screen area and more health sensors than the SE.

Apple Watch SE specs

Both the second-generation Apple Watch SE and Apple Watch Series 9 run watchOS 10 and will be compatible with the upcoming watchOS 11, so you don’t have to worry about either being obsolete anytime soon.

Product specifications

Size: 40 to 44 mm | Battery Life: 18 hr | Case material: Aluminum | Processor (Apple S-series): S8 | Storage Capacity:  32GB

The Apple Watch SE, in its second generation, is available in either 40 or 44-millimeter sizes and in both GPS (Wi-Fi and Bluetooth only) and GPS + Cellular (Wi-Fi, Bluetooth and cellular) models. The SE’s case is made out of satin-finish aluminum in three colors, with Ion-X glass in front and a nylon-based back.

It runs on Apple’s S8 all-in-one system-in-package (SIP) with up to 32GB of storage. Its high-resolution Retina touch screen reaches up to 1,000 nits of brightness that comes on when you raise your wrist or touch the watch. It sports Apple’s Digital Crown control with haptic feedback, plus a large multipurpose button. It’s waterproof to 50 meters, enough to be used for pool sports and swimming, and has sensors for tracking motion, distance and heart rate.

Apple Watch Series 9 specs

The Apple Watch Series 9 has more expensive materials and finishes than the Apple Watch SE.

Product specifications

Size: 41 to 45 mm | Battery Life: 18 hr (32 hr low-power mode) | Case materials: Aluminum or stainless steel | Processor (Apple S-series): S9 | Storage Capacity: 64GB

The Apple Watch Series 9 comes in slightly larger case sizes, 41 or 44 millimeters, made out of satin-finish aluminum or polished stainless steel in four colors. Its touch screen has more display area than the SE’s, with much thinner bezels, and gets up to twice as bright at 2,000 nits maximum. It has always-on capability as well, letting you show off your chosen watch face whether or not your wrist is raised. The face of the stainless steel Watch 9 models is tough sapphire as well.

Inside is Apple’s S9 SIP with 64GB of storage and the ability to run Siri locally for greater privacy and functionality; its speed made switching between apps and all app functions visibly smooth and fluid during testing. It’s equally waterproof and has additional sensors that let it measure ECG and temperature as well as heart rate and motion.

Key differences

• Materials: The Apple Watch Series 9 has more expensive materials and finishes than the Apple Watch SE, such as stainless steel and sapphire glass.
• Always-on screen: The Series 9’s screen can be set to be always turned on, letting you show off your watch face even if you’re not interacting with it. The SE’s screen only comes on if you raise your wrist or tap the watch.
• Size and display area: The Series 9 comes in slightly larger case sizes than the SE, and its screens at both sizes extend further to the edges and pack more display area than the ones on the SE.
• Advanced health features: The Series 9 has sensors for a single-lead ECG and body temperature, which the SE lacks.
• Haptic touch: The Series 9 can be controlled by haptic touch, where tapping your fingers together registers as a control command for the watch. The SE lacks this feature, although it does have similar gestures in its Accessibility control panel.

Key similarities

• Waterproofing: Both the Apple Watch Series 9 and SE are waterproof enough to be used in the shower or the pool.
• Fitness and sleep tracking: The Series 9 and SE can track heart rate, distance and motion to gauge your fitness and track your activity or workouts, and you can use this info to track sleep stages and quality if you wear it overnight.
• WatchOS: Both the Series 9 and second-generation SE support the same watchOS versions with almost all the same apps and features, such as navigation, calculator, timer and iPhone mirroring.
• GPS or cellular: Both the Series 9 and SE come in either GPS (Wi-Fi and Bluetooth only) or GPS + Cellular (with a built-in cellular radio for phone calls and data) models.

Design and materials comparison

Both the Apple Watch Series 9 and Apple Watch SE look alike. They have a squarish body with softly curved sides and corners, a Digital Crown and button on one side, vents for speakers and water expulsion on the other, and removable, swappable bands or straps.

Both come in two sizes for smaller or larger wrists. The Series 9 is 1 millimeter larger in both sizes than the SE (41 and 45 millimeters compared to 40 and 44 millimeters, respectively). The Series 9’s case can be made either of more affordable, satin-finished aluminum or stronger, heavier polished stainless steel. The back is made of ceramic, and the glass of the face is either ion-X glass (for the aluminum cases) or sapphire (for the stainless steel cases). The Series 9 comes in five colors: Midnight, Space Gray, Silver, Starlight and Red.

The SE is only made of aluminum in a satin finish, in Space Gray, Silver or Starlight. It has an ion-X glass face and a back made of nylon plastic. We found in our testing that the ion-X glass could sometimes be gouged or scratched during use, although we never managed to actually shatter it.

Display comparison

The difference between the Apple Watch Series 9 and SE comes across clearly when you look at their displays. The Series 9, in both case sizes, has an edge-to-edge display that extends past the curve of the front glass. The SE’s display has thicker bezels and a smaller display area, 759 square millimeters for the 40-millimeter case and 977 square millimeters for the 44-millimeter case. Compare this to the Series 9, with 904 square millimeters for the 41-millimeter case and 1,143 square millimeters for the 45-millimeter case. This means the smaller 41-millimeter Series 9 model has a display area closer to that of the 44-millimeter SE than the 40-millimeter option.

Another major difference between the two models is the Series 9’s always-on screen. It looks and feels more like a classic watch that shows a face at all times, even when not in use. We think this is a great way to make a fashion statement or accessorize with a watch face of your choice. The Apple Watch SE’s screen only comes on if you lift your wrist or interact with it. Otherwise, it’s a blank black square.

A third major difference is brightness. Not only is the Series 9’s screen capable of reaching 2,000 nits in brightness, it also can go as low as 1 nit in the dark. We found this feature helpful when we tested it at night in a pitch-black room, making the face and screen still legible without disturbing your nighttime vision. The Apple Watch SE doesn’t have this ultra-low-light feature and gets only as bright as 1,000 nits. But that’s still much brighter than most laptop screens and about as bright as most cell phones.

Health features comparison

All Apple Watches share basic motion- and fitness-tracking capabilities, but the Apple Watch Series 9 has more sensors and can track more readings than the SE.

Heart rate

Both the Apple Watch Series 9 and Apple Watch SE have heart rate sensors that shine a green light against your skin to estimate how fast your blood is pumping. Both heart rate sensors are generally accurate, although strap tightness, watch location, and most importantly, skin color can affect your results.

We compared the heart rate readings of the Series 9 and SE to other sensors and found them accurate for fitness purposes, but, like most of Apple’s health sensors, it shouldn’t be considered a replacement for a medical-grade heart rate sensor. The Series 9’s heart rate sensors are considered third generation for Apple, while the SE’s are second generation.

ECG

The Apple Watch Series 9 can take a one-lead electrocardiogram. This can be helpful for people with cardiac issues and can show whether your heart has a good sinus rhythm. Again, it’s not meant to be a replacement for professional medical tests; an ECG at your doctor’s office uses 12 leads by comparison. The Apple Watch SE lacks ECG sensors.

Sleep tracking

The Apple Watch Series 9 and Apple Watch SE can track your sleep habits and quality, using their motion and heart rate sensors to detect resting heart rate, sleep stages, breathing rate and time spent in bed. We found this feature detailed and informative during our tests, especially its breakdown of sleep stages into deep, core, REM and wakefulness (although we found wearing a watch to bed every night may be annoying for some people). Happily, we noted that even if you don’t wear your Apple Watch while you sleep, it still estimates the amount of time you spend in bed.

Body temperature and menstrual cycles

If you need to track menstrual cycles, both the Series 9 and SE can feed information to Apple’s Health app for privacy. The Series 9 can also use its body temperature sensor to not only monitor body temperature overall but also estimate retrospective ovulation and fertility. The SE lacks a body temperature sensor.

Other tracked metrics

• Steps: Both models can track how many steps you take, not just in total but also per activity and even moment to moment.
• Distance: Both models use their sensors to track where and how far you move.
• Stairs: Both the Series 9 and SE can estimate how many flights of stairs you’ve climbed.
• Balance: Both watch models can monitor your gait, position and double support time to estimate your sense of balance and alert you of any changes.
• Cardio fitness (VO2): Both models can help estimate your cardiovascular fitness or VO2 scores from the data they gather, but the results aren’t as accurate as those taken in a doctor’s office or other controlled cardio test environment.

About Blood O2

Due to a lawsuit and injunction, Apple isn’t currently allowed to sell devices that measure blood oxygen levels or blood O2 in the United States. This means the Apple Watch Series 9 and Ultra 2 in the United States have had their blood O2 features deactivated. If you live outside the U.S., you can buy the Series 9 with blood O2 capability. The Apple Watch SE doesn’t measure blood O2.

Apple Watch Series 9 vs. SE: Other features

Health and fitness tracking aren’t all an Apple Watch can do. Both the Apple Watch Series 9 and Apple Watch SE have a plethora of functions and capabilities that come in handy in everyday life.

Watch faces and time

Both the Apple Watch Series 9 and Apple Watch SE support a variety of digital watch faces, from the informative to the fashionable to the fun. The Series 9 has faces optimized for its always-on display and ultra-low-light capability, showing simplified or highly legible features when not in active use that become more complex and full-featured when the watch is raised. The larger display area of the Series 9 makes faces look bigger and fuller compared to the black bezels around the SE’s display.

Maps and navigation

The Series 9 and SE have full-featured Maps apps that not only show where you are but can give turn-by-turn directions and routing with haptic feedback. The Maps app on both models can also show terrain for runners and hikers. The bigger screen and fuller display of the Series 9 can show more information than that of the SE.

Notifications

We found in our experience that one of the most useful abilities of an Apple Watch is simply giving you notifications without having to look at your phone. All Apple Watch models let you know if you’ve got an email, a message, a social media alert, weather alerts, appointments, reminders, timers and anything else you may want to be informed about.

Messaging and calling

Both the Apple Watch Series 9 and Apple Watch SE can show messages from a paired iPhone, including Apple’s own Messages app and third-party apps like Messenger or WhatsApp. You can even respond to them on your watch by dictation, handwriting recognition, or on the Series 9, an on-screen keyboard. We found this to usually be a hassle on such a small screen, and instead preferred emojis or prewritten responses the watch supplies.

Both models can be used for calling as well, either in conjunction with a paired iPhone or on their own in the GPS + Cellular models. In our testing, we found their speakers and mics adequate for calls.

Siri

The Series 9’s S9 chip allows Siri to run a lot of its functions on the watch itself rather than from a paired phone. In our tests, Siri was faster and more responsive on the Series 9 than on the SE, and running locally had access to more private information, like health stats and metrics. Siri is slower and less powerful on the Apple Watch SE.

Haptic touch 

The Apple Watch Series 9 introduced haptic touch, which allows you to respond to the watch by means of tapping your thumb and forefinger together. We found this to be very convenient when responding to notifications while both hands were occupied, such as when carrying bags. The Apple Watch SE has a similar capability as part of Assistive Touch, one of the Accessibility features of watchOS, but it wasn’t as precise or universal when we used it compared to haptic touch.

Price

The Apple Watch SE is Apple’s lowest-cost Apple Watch model, starting at $249 for the 40-millimeter GPS model and $329 for the 44-millimeter GPS model. The Apple Watch Series 9, on the other hand, has two pricing tiers. Models with aluminum cases start at $399 for the 41-millimeter GPS model and $429 for the 45-millimeter version, while models with stainless steel cases and sapphire faces start at $749 and $799 for the 41-millimeter and 45-millimeter cases, respectively. 

Bottom line

There’s no mistaking the Apple Watch Series 9 for anything but a flagship smartwatch. It has the processing power, always-on screen, advanced sensors and premium materials that make it both a personal device and a fashion accessory. If you can afford it, you won’t be sorry.

However, we’ve found that the lower-cost Apple Watch SE does almost everything we need a smartwatch to do daily. For people who want the Apple Watch experience but don’t need the most advanced features, including seniors or children, the Apple Watch SE is the better value.

Prices listed reflect time and date of publication and are subject to change.

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