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Garmin Forerunner 225 review: A great running watch with accurate heart-rate tracking

Garmin's first watch to include a wrist-based heart-rate monitor also has all the bells and whistles runners look for.

Dan Graziano Associate Editor / How To
Dan Graziano is an associate editor for CNET. His work has appeared on BGR, Fox News, Fox Business, and Yahoo News, among other publications. When he isn't tinkering with the latest gadgets and gizmos, he can be found enjoying the sights and sounds of New York City.
Dan Graziano
8 min read

Editors' note, April 15, 2016: The Garmin Forerunner 225 has been replaced by the Forerunner 235. Read our full review here.


Garmin Forerunner 225

The Good

The Garmin Forerunner 225 has an always-on display, accurate GPS for tracking runs, a wrist-based heart-rate monitor, and can track steps and calories. It's water-resistant and can be worn in the shower and pool.

The Bad

Heart-rate tracking is limited to workouts, there's no automatic syncing, sleep data lacks detailed information, and Garmin's mobile app is dated.

The Bottom Line

Runners interested in tracking both heart-rate and all-day activities can't go wrong with the Forerunner 225.

Over the past year, an influx of dedicated fitness gadgets have included both GPS and heart-rate sensors. The Microsoft Band and Fitbit Surge may come to mind.

Until now, Garmin's stayed out of the wrist-worn heart rate territory -- the company's previous watches required pairing a separate chest strap to track heart rate. The $300 (£240, AU$389) Garmin Forerunner 225 changes that once and for all. This watch is Garmin's first to include a wrist-based heart-rate sensor, but that's not all.

This is a runner's watch. It has both built-in GPS for pace and distance tracking, as well as all-day activity tracking. I've been hesitant to embrace these wrist-based heart-rate sensors, assuming they would lack accuracy, but the Forerunner 225 has helped change my mind. It's also one of my favorite running watches from a design standpoint, falling just behind Garmin's ultra-slim Vivoactive smartwatch .

The Forerunner 225 adds a lot of new features to a great running watch. It's the running watch I would personally buy. Is it perfect? No, but this comes closest to meeting my needs.

What it does

The Forerunner 225 is an all-day activity tracker, running watch with GPS, and heart-rate monitor all wrapped up into a single device.

Sarah Tew/CNET

The GPS is used to accurately measure pace and distance when running outdoors. Thanks to the optical heart-rate sensor on the back of the watch, you can track beats per minute both during workouts, and whenever you'd like to start measuring it during the day. The advantage of optical wrist-based heart rate monitoring is you get to skip wearing a chest strap monitor. The drawback, in many cases, is that wrist-based monitoring ends up being less accurate. This Garmin's optical heart rate measurements were a lot better than most.

This Garmin watch also has an accelerometer for tracking all-day activities. It can measure steps, distance traveled and calories burned. It can also automatically measure your sleep at night, but it doesn't provide detailed information on sleep cycles or how long it took for you to fall asleep

Sarah Tew/CNET

The accelerometer also handles indoor distance tracking when GPS isn't available. It works, but isn't as accurate as using GPS. When compared to the treadmill's distance measurements, I found indoor runs to be off by around 0.05 to 0.10 mile.

The Forerunner 225 also has inactivity alerts that will remind you to get up and move after an extended period of inactivity, as well as a vibrating alarm. The Forerunner is a nice everyday wristwatch, too. The only thing it's missing are smartphone notifications, like those found on the Fitbit Surge or Apple Watch.


In the past, I have argued that most GPS running watches wouldn't be comfortable enough to be worn throughout the day. They tend to be big eyesores. While the Forerunner 225 is big and bulky, in a certain light it can be somewhat beautiful -- at least on a man's wrist, as the watch measures 48mm across. For comparison, the largest Apple Watch model is only 42mm. It has about the size and thickness of a Casio G-Shock. It's also only available in a single color: black with red accents.

Sarah Tew/CNET

It's nice not having to take the watch off when I take a shower or go for a swim. The Forerunner 225 carries a water resistance rating of 5 ATM, which means it can withstand pressure of up to 50 meters. (You can learn more about water resistance ratings in watches and activity trackers here.)

I also like the watch's color display. It's always on, so there's no need to tap the screen or flick your wrist to view the time and date. You won't have an issue reading it outside, even when in direct sunlight. Indoors or in low-light situations it could be a bit dull, but there's a backlight.

The Forerunner 225 compared to similar running watches. From left to right: Runsense SF-810, Forerunner 225, Fitbit Surge, Adidas MiCoach Smart Run. Sarah Tew/CNET

The watch held up well over the course of my testing. I ran with it more than a dozen times in situations ranging from extreme heat to torrential downpour. There were even a few times I accidentally hit the face of the watch against the wall. It held up well until I tripped and fell on a recent run. There is now a small scratch on the screen. Clumsy runners, beware.

Heart-rate monitor: Continuous and accurate during workouts

Garmin partnered with Mio to provide the optical heart-rate sensor on the Forerunner 225. The technique it uses is similar to what is found in the Fitbit Surge and Apple Watch. A flickering LED green light is used to light the capillaries, which allows the sensor on the back of the watch to measure the blood as it flows by.

The process to acquire my heart rate was nice and quick, although times will vary depending on the temperature. In colder weather these optical sensors can have a more difficult time locking onto your heart rate.

Sarah Tew/CNET

In order to test the accuracy of the heart-rate sensor, I ran with both the Forerunner 225 and a Polar H7 Bluetooth chest strap for a little over 20 minutes. I then compared the data that was recorded on both devices. Using the chest strap as an accepted baseline, I found the Forerunner 225 to be incredibly accurate.

The watch measured my average beats per minute at 174 and maximum heart rate at 203 bpm. These results were only a single beat off from the chest strap, which measured me at an average of 175 bpm and a maximum heart rate of 204 bpm. You can view the full data from my workout below.

Enlarge Image
Heart rate information recorded on the Garmin Forerunner 225. Screenshot by Dan Graziano/CNET
Enlarge Image
Heart rate information from the Polar H7 chest strap. Screenshot by Dan Graziano/CNET

Unfortunately, the heart-rate tracking on the Forerunner 225 is limited to workouts and on-demand checks. It isn't like the Fitbit Charge HR , which runs continuously throughout the day. This means that the heart-rate sensor on the Forerunner 225 isn't being used to improve the accuracy of calorie burn or sleep measurements.

Running is an enjoyable experience

The GPS in the Forerunner 225 was quick and reliable. It took anywhere from 30 seconds to a couple of minutes to acquire a signal. That's pretty good for this type of watch in a big city. It performed even better in the suburbs of New Jersey, acquiring the GPS signal within a couple of seconds.

I did notice that the watch had some trouble mapping out direct routes on the streets of New York City, but this is a common urban problem that affects GPS devices. Once I reached an open area, such as Central Park or along the East River, the GPS was spot-on.

Sarah Tew/CNET

It was easy to view all of my data without missing a step. There are two workout screens with three lines that can be customized with different data points. A third screen will display your heart rate, while the time and data will appear on the fourth screen. There are 14 data points to choose from: timer, lap time, distance, lap distance, pace, average pace, lap pace, speed, cadence, calories, heart-rate, average heart-rate, HR zones and elevation.

Heart rate information can be confusing, but Garmin did good job at explaining it with the Forerunner 225. The watch has a color gauge that shows what heart rate training zone you are in when working out. When it's gray, you're in the warm-up zone; blue is the easy zone; green is aerobic; orange is threshold; and red is your maximum zone. The Forerunner 225 estimates each heart rate zones based on age, but you can adjust each zone manually through the company's mobile app.

Sarah Tew/CNET

The Forerunner 225 includes Auto Pause, which will automatically pause the watch when you stop (for example, at a busy intersection), and Auto Lap, which will automatically record lap data when you reach a specific distance. There's also interval training for creating custom workouts. This let's you set a specific distance or time, a rest period, the amount of reps you want to do, and a warm-up and cool down.

When you complete a run, the watch will provide you with a summary of your workout. This includes information on your pace, distance, calories burned, average heart rate, maximum heart rate, cadence and elevation. You can also look back at the pace you hit on each lap, a feature seasoned runners will appreciate.

Battery life

Garmin states that the Forerunner 225 will last up to 10 hours with an active GPS signal and the optical heart-rate sensor turned on. If you were to use the watch solely as an activity tracker, Garmin claims it will last up to four weeks.

Sarah Tew/CNET

I saw about a week and a half of battery life, which included five runs between 30 and 40 minutes. Your battery life will vary based on how often you use the GPS.

In what has become the norm in the wearable industry, the 225 uses a proprietary dock for charging and syncing data with the computer.

Android and iOS support

The Forerunner 225 includes Bluetooth for syncing data with an Android and iOS device, but it doesn't do so automatically. In order to save battery life, the phone and watch don't maintain a constant Bluetooth connection. This means when you want to sync data, you must press the red button on the watch and wait for it to connect. The syncing process isn't necessarily slow, but I miss the convenience of having automatic uploads in the Garmin Vivoactive.

Sarah Tew/CNET

Data from past runs, including a map of your workout and charts for heart rate and pace, can be viewed on the Garmin Connect mobile app or website. Here you can also view your step history, calorie burn and sleep over the past few days, weeks and months.

Sarah Tew/CNET

The app has me a bit torn. I like that it can connect with MyFitnessPal to help monitor calorie intake, and I find the running data to be adequate. It's when you start to view your activity data that you see just how far behind the Connect app is compared to Fitbit and Jawbone.

Other companies attempt to estimate the amount of deep and light sleep you achieve each night, along with how long it took to fall asleep and how many times you woke up. Garmin's solution shows a graph of movement throughout the night and that's it. Jawbone also offers up smart coaching tips and feedback to help users better achieve their fitness goals and maintain a healthy lifestyle. Garmin Connect does not.

Sarah Tew/CNET

One feature I have always liked with Garmin devices are the personalized activity goals. Each day the goal for steps will automatically adjust depending on your performance the day before. This makes it easy for new users to work their way up to reaching (and eventually surpassing) the traditional 10,000 step goal.


Sarah Tew/CNET

The Forerunner 225 isn't for those people who want a basic activity tracker. You know, the "I need a Fitbit" crowd. If that's you, you would be better off with a Fitbit Charge, Jawbone Up2 or Garmin Vivofit 2 . On the other side of the spectrum, not all runners will want heart-rate and activity tracking in their GPS watches. If that's the case, you should check out the cheaper Forerunner 220. It's essentially a Forerunner 225 without the extra bells and whistles.

If you want an accurate GPS running watch that is also capable of measuring heart rate and all-day activity tracking, you can't go wrong with the Forerunner 225.

You won't be feeling buyers remorse. The Forerunner 225 is one of the better running watches on the market. It's not perfect, but for the price it covers what I need better than any previous running watch before.


Garmin Forerunner 225

Score Breakdown

Design 8Battery 8Performance 9Software 6Features 9