The battery life of smartwatches varies significantly more than with other technology products like smartphones, tablets, and laptops.

Their relatively small batteries have to juggle power and efficiency as LTE, GPS, Bluetooth, and Wi-Fi fight for energy with heart rate monitors, accelerometers, barometers, and a display expected to show the time constantly.

Generally speaking, more functionality equates to shorter battery life. As such, feature-packed smartwatches from Apple and Samsung must be placed on their charging docks daily, while hybrid watches like those from Withings can last 25 days.

The Wyze Watch is a $20 device that promises a nine-day battery life. Primarily a smart home company, Wyze has yet to provide more details on the battery life, but the watch's lack of energy-sapping GPS, LTE, and music streaming will play a vital role here. We'll be keen to review.

As an example of how much GPS and 5G can affect a smartwatch battery, look at Apple's claims for the Watch Series 8.

The company states 18 hours of battery life is possible during a typical day, which includes 180-time checks, 180 notifications, 90 minutes of app use, and a 60-minute workout with music playback over Bluetooth.

But if you take a call over the Watch's LTE connection, the battery will die after just 90 minutes, and recording outdoor exercise with GPS and LTE active will kill the watch in five hours. (We've seen similar results with the Apple Watch in our testing.)

You should consider all this when buying a new smartwatch, and while your personal usage stats will vary, it is interesting to see just how much variation there is in the manufacturer's claims. Here we have gathered up six smartwatches whose claimed battery life (while used as a proper smartwatch and not in a battery-saver mode) ranges from 18 hours to 173 days.

Garmin Fenix 7: 173 days with Solar

The Garmin Fenix 7 has a claimed 22-day battery life with solarGarmin

The current king of smartwatch battery life is the Garmin Fenix 7, which claims to have 22 days of use.

The new Fenix 7 is a huge watch with a 47mm case, likely an acquired taste for many. But that large case means a big battery and tough build quality with waterproofing to 100 meters. As well as acting like a smartwatch and fitness tracker, the watch has ski maps for 2,000 resorts worldwide, animated workout guides, an expedition mode, advanced run tracking, and data for 43,000 golf courses.

Garmin claims 22 days of smartwatch use with solar or 173—days of use when on battery-saving mode and solar power. When music is played simultaneously, the battery life goes to 10 hours, while a special, energy-sipping 'Expedition GPS Mode' can last up to 40 days, and the battery-saver mode is good for a claimed 74 days.

Garmin fenix 7X Sapphire Solar, Larger sized adventure smartwatch, with Solar Charging Capabilities, rugged outdoor watch with GPS, touchscreen, wellness features, black DLC titanium with black band

List Price: $969.00

New From: $959.49in Stock

Used From: $850.00in Stock

Garmin Forerunner 965: 23 days

The Garmin Forerunner 965 has a claimed 23-day battery lifeGarmin

Another option from Garmin is the Forerunner 965, a fitness-focused smartwatch that mixes advanced exercise tracking and health data collection with smartwatch features like calls, notifications, contactless payments, and music streaming. The Forerunner 965 also has a heart rate monitor, an oxygen saturation sensor, hydration tracking, sleep monitoring, and an app for checking stress levels.

Exercise features include the Garmin Coach app for helping you with 5K, 10K, and half-marathon runs and a set of on-screen workout animations.

Despite the many features, Garmin says the Forerunner has a battery life of 23 days in "smartwatch mode," which should be achievable when using the watch as normal and not restricting it to a state where it only shows the time. Garmin says up to 10.5 hours of battery life is possible with GPS enabled while streaming music.

Garmin Forerunner® 965 Running Smartwatch, Colorful AMOLED Display, Training Metrics and Recovery Insights, Black and Powder Gray

List Price: $599.00

New From: $599.99in Stock

Fitbit Versa 4: Six days

Fitbit Versa 4 provides 6+ days of usage on a single charge. Fitbit

Another fitness smartwatch with strong battery life is the Versa 4 by Fitbit. This watch has all the exercise and fitness tracking features you would expect from Fitbit, built-in GPS for recording outdoor runs, music playback, sleep tracking, and a choice of Amazon Alexa or Google Assistant.

It also has a 24/7 heart rate monitor and can calculate your oxygen saturation level. The watch can handle calls and texts via your smartphone, includes Fitbit Pay for contactless credit card payments, an always-on display, and there are three color options to pick from.

Fitbit says the Versa 4 has a battery life of six days, during which time it will track your movement all day and night. The company says battery life "varies with use and other factors; up to 12 hours with continuous GPS."

Fitbit Versa 4 Fitness Smartwatch with Daily Readiness, GPS, 24/7 Heart Rate, 40+ Exercise Modes, Sleep Tracking and more, Black/Graphite, One Size (S & L Bands Included)

List Price: $194.99

New From: $194.99in Stock

Mobvoi TicWatch 5 Pro: More Than Three days (80 hours)

The TicWatch 5 Pro and its dual-display system have more than a three-day battery lifeTicWatch

Falling a little behind the Fitbit is the TicWatch 5 Pro by Mobvoi. This smartwatch uses the industry-leading Snapdragon W5+ Gen 1 Wearable Platform and is powered with the latest version of Wear OS by Google. It functions like any other smartwatch with fitness, sleep, and activity tracking.

There is also a heart rate monitor, blood saturation tracking, Skin Temperature Sensor, IP68 waterproofing, making it safe to swim with, integrated GPS, barometer, compass, and an altimeter.

What's clever here is how the TicWatch 5 Pro has two displays. First, there is a regular AMOLED display, similar to the screens of other smartwatches; above that sits a low-power display that is transparent when not in use and looks like a Kindle ebook reader. This means the low-power, greyscale display can be used to show the time constantly, then the color display beneath shines into life when you want to do more.

It's a clever setup that means the TicWatch can last 45 days when using only the low-power screen. Mobvoi claims up to 80 hours or more than three days of battery life when using both. It also works on Bluetooth and Wi-Fi (2.4 GHz) wireless connections.

Ticwatch Pro 5 Android Smartwatch for Men Snapdragon W5+ Gen 1 Platform Wear OS Smart Watch 80 Hrs Long Battery Life Health Fitness Tracking Built in GPS 5ATM Water Resistance Compass NFC Mic Speaker

List Price: $349.99

New From: $349.99in Stock

Samsung Galaxy Watch 5: 50 hours

The Galaxy Watch 5 has a claimed 50-hour battery lifeSamsung

Samsung's latest smartwatch, the Galaxy Watch 5, has a sleek design, the company's own Tizen operating system, and is a worthy rival to the Apple Watch. Available in 40mm and 44mm case size options, the watch can be fitted to any strap thanks to industry-standard lug bars and is available in silver, pink gold, and graphite.

There is an NFC for contactless payments, Bluetooth for music playback, constant heart rate tracking, sleep coaching, IP68 water resistance, and a suite of exercise and fitness apps to log every exercise session.

Samsung is a little vague on battery life, stating that 50 hours is possible with "typical usage" and up to 131 hours (5.5 days) can be achieved with "low usage." The company also says: "Actual battery life varies by network environment, features and apps used, frequency of calls and messages, number of times charged, and many other factors." However, the smartwatch does come with a fast charge.

SAMSUNG Galaxy Watch 5 40mm Bluetooth Smartwatch w/ Body, Health, Fitness and Sleep Tracker, Improved Battery, Sapphire Crystal Glass, Enhanced GPS Tracking, US Version, Silver Bezel w/ Purple Band

List Price: $229.99

New From: $229.99in Stock

Used From: $211.59in Stock

Apple Watch Series 8: 18 hours

Apple Watch 8 Series offers 18 hours of battery life Apple

As we mentioned earlier, the Apple Watch doesn't have a particularly long battery life compared to the claims of others. However, Apple goes into more detail than most regarding what an average 18-hour day with a Watch might look like, as explained earlier.

The Watch Series 8 is as feature-packed as smartwatches get, with Wi-Fi, Bluetooth, GPS, and optional 5G, plus activity tracking, heart rate, and sleep. It can also take an ECG, monitor blood oxygen saturation, make an emergency call if you fall over and don't get up, and it can be worn while swimming.

It does a lot but requires daily (or nightly) charging. This is primarily okay when used during the day, but if you want to track your sleep with an Apple Watch 8, you'll have to work out a routine where its battery is topped up at some point during each day.

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Apple Watch Series 8 [GPS 41mm] Smart Watch w/Midnight Aluminum Case with Midnight Sport Band - S/M. Fitness Tracker, Blood Oxygen & ECG Apps, Always-On Retina Display, Water Resistant

List Price: $329.00

New From: $329.00in Stock

Used From: $313.86in Stock

Check out The GearBrain, our product find engine to see the other smartwatches that work with your smartphone or your Google Assistant and Amazon Alexa-enabled devices.

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