Apple Watch Ultra vs. Series 8: Which should you buy?

The Apple Watch Series 8 is the standard Apple Watch that you've come to know and love over the years. It has a few new features, like Crash Detection and a processor that's about 20% faster than previous generations. It's admittedly not as exciting of a new product as the super rugged Apple Watch Ultra, which you can even go diving with, but that doesn't mean that you automatically should get the Apple Watch Ultra. Let's dive into the specific differences to see which watch is right for you. 

Apple Watch Ultra vs. Series 8: Design, colors, and finishes

(Image credit: Apple)

To start, our Apple Watch Series 8 review notes that the latest model carries the same design as the previous generation. It comes in two case sizes —  41mm and 45mm — and offers aluminum or stainless steel finishes. The aluminum comes in four colors, Midnight, Starlight, PRODUCT(RED), and silver; while the stainless steel comes in silver, gold, and Graphite.

Of course, the Apple Watch Ultra is a whole different story offering a brand new rugged design we haven't seen on the Apple Watch before. It's got a 49mm case, so the screen is larger than the biggest Series 8, and it's completely flat. The Ultra also looks a far bit different thanks to its extra protection around the Digital Crown and Side button on the right side of the watch.

Over on the other side of the watch, there's a new Action button. It's a customizable button that can offer one-touch access to many features. Apple specifically mentioned the ability to start a workout or move to the next interval of a custom workout, but we expect it can do a lot more than we know right now.

The Apple Watch Ultra only comes in a titanium case and one color, meaning you have fewer options for personalization.

Apple Watch Ultra vs. Series 8: Internals and specs

(Image credit: Apple)

You may notice that both the Apple Watch Ultra and Series 8 have the exact same chip — the S8 — which means both models are going to be faster than the watches that came before them. When it comes to sensors — like the new temperature sensors — both watches have them, but there are some more subtle differences that we can point out in the spec sheet. 

Swipe to scroll horizontally
Header Cell - Column 0 UltraSeries 8
Case sizes49mm41mm and 45mm
Battery life36 hours (up to 60 hours) 118 hours (up to 36 hours)
Screen brightness2000 nits1000 nits
Water resistance100m, swimproof and recreational dive to 40m50m, swimproof
Always-On displayYesYes
GPSPrecision dual-frequency (L1 & L5) GPS L1 GPS
CellularIncluded in every modelCellular models available
Night modeYesNo
Crash/Fall DetectionYesYes
Temperature SensorYesYes
Low Power ModeYesYes
Starting price$799$399

Apple Watch Ultra vs. Series 8: Display and features

Apple Watch Ultra in dark red light

(Image credit: Apple)

The brightness difference between the two models looks stark, with the Apple Watch Ultra being twice as bright as the Series 8. This will make it much easier to see the screen in direct sunlight or other bright conditions. That's not the only trick the Ultra has up its sleeve, as the new Night mode will make it easier for your eyes to see the screen in the dark by turning the display dark and red. However, both do come with an always-on display.

You'll notice that the Ultra also has better GPS, meaning you'll likely get a more precise location from your Ultra than you would on the Series 8. However, both employ Backtrack, which quite literally helps you backtrack your steps — important if you're out in the wilderness.

Both the Series 8 and Ultra have an IP6X dust resistance, but that's about where the similarity in terms of ruggedness end.

Both the Apple Watch Series 8 and the Apple Watch Ultra have an IP6X dust resistance, but that's about where the similarity in terms of ruggedness end. The Ultra is water-resistant up to 100m (twice as much as the Series 8) and can even withstand recreational diving up to 40m. Additionally, the Ultra has been tested MIL-STD 810H, which includes testing for altitude, low and high temperatures, rain, sand, freezing and thawing, and more. Plus, the Ultra will function just fine in some pretty extreme temperatures with a range between -4° F (-20° C) – 131° F (55° C), according to Apple. In other words, the Ultra is designed to go with you literally everywhere and will withstand a lot more abuse than the Apple Watch Series 8 can.

By now you likely understand that the Apple Watch Ultra caters to adrenaline junkies who may find themselves in some tricky situations. In these cases, the Ultra can help come to the rescue. Both the Series 8 and Ultra offer SOS emergency calling, as well as Crash and Fall Detection, with each respective watch being able to notice you've fallen or been in a car crash, and then promptly notifying authorities and reaching out to your emergency contacts. However, it's the Ultra that goes a step further. It has an 86-decibel siren that can sound off, alerting people up to 600 feet away that you need help through a unique sound signature.

Apple Watch Ultra vs. Series 8: Battery life

(Image credit: Apple)

As expected, the Apple Watch Ultra will provide you with more battery life. The Series 8 has an 18-hour battery life, while the Ultra doubles that to 36 hours. That's running normally. Thanks to the fact that the Apple Watch Series 8 and Apple Watch Ultra will run watchOS 9, Low Power Mode will be on both devices (a feature our watchOS 9 review said "made me love the Apple Watch again").

Low Power Mode will push the Apple Watch Series 8 to 36 hours of battery life, while the Ultra can get up to 60 hours. That's with Low Power Mode enabled on both as well as special low power settings coming specifically to the Apple Watch Ultra. However, it seems that the low-power setting will not be available at launch, and Apple says it will be available later this fall, so keep that in mind. 

Apple Watch Ultra vs Series 8: Which should you buy?

(Image credit: Apple)

At $799, the Apple Watch Ultra seems like a great price, but as always, which is the best Apple Watch for you will largely depend on why you want an Apple Watch.

Are you an explorer who wants an Apple Watch to take with you when hiking, diving, mountain climbing, or other adventurous activities? It seems like the Apple Watch Ultra would be the best fit for you, especially if you love the idea of having 60 hours of battery power to play around with. However, not everyone is so adventurous.

The Apple Watch Series 8 is the upgrade you'd expect. It has all the health tracking features you want, plus the addition of a temperature sensor and Crash Detection. It's likely the best Apple Watch for most people who don't mind being less adventurous.  

Luke Filipowicz
Staff Writer

Luke Filipowicz has been a writer at iMore, covering Apple for nearly a decade now. He writes a lot about Apple Watch and iPad but covers the iPhone and Mac as well. He often describes himself as an "Apple user on a budget" and firmly believes that great technology can be affordable if you know where to look. Luke also heads up the iMore Show — a weekly podcast focusing on Apple news, rumors, and products but likes to have some fun along the way. 

Luke knows he spends more time on Twitter than he probably should, so feel free to follow him or give him a shout on social media @LukeFilipowicz.