How to choose a swimming watch

What features should you look out for in a swimming watch? We polled our readers about what they found most useful and what they could do without

When I started swimming, the only means of keeping track of time was the pace clock, and the only way to know how far you had swum was to count. We measured our heart rates manually.

Now, modern sports watches boast so many features that it can be confusing to know what’s most useful for swimmers. We therefore ran a survey to ask swimmers which functions they felt were the most important.

• Read our review of the best swimming watches for 2024

What we want from a swimming watch in open water

In open water, distance measurement with GPS was by far the most important. Then came pace, distance notifications and heart rate, with the latter scoring much lower than we expected as can be seen in chart 1. 

Secondly, we asked what other features people use. Top of the list was the most obvious: they use it to record how long they are in the water for! The other feature people liked was a thermometer. 

Finally, we asked what features people would like that they didn’t have. Popular requests included water temperature, a longer battery life, audible feedback through bone conduction headphones, and more accurate GPS. Note that some of these features are available on certain models.

How accurate is my watch GPS for swimming?

You may have experienced swimming side by side with a friend but recording very different distances. GPS isn’t always accurate while swimming. In our survey, we asked how accurate our readers felt their GPS watches are, based on their experience. As you can see, there’s a wide range.

However, there are things you can do to improve the accuracy. Garmin recommend ensuring your watch is synced to your phone, waiting a minute after your watch has acquired GPS signal before swimming, not swimming breaststroke and keeping the watch above the surface of the water if you stop (as GPS signal cannot travel through water). Alternatively, and especially if you swim breaststroke, you could put your watch on your head under a swim cap. Newer models may also be more accurate.

What swimmers want in the pool

Top of the wish list for pool swimmers was length counting. Swim speed came next, closely followed by lap time, stroke rate, total elapsed time and interval time. These metrics are almost universally available. Heart rate was again a long way down the list with no respondents ranking it as first choice and only 8% as second. Stroke detection and distance per stroke were bottom of the list. See chart 2.

Other features swimmers say they regularly use include the drills setting, repeat timer, critical swim speed (CSS) alarm and calorie counter. 

On the wish list for pool swimmers are features that measure your stroke dynamics, wrist-based heart rate monitoring, a pacing metronome and better length counting accuracy.

One reader noted that it’s annoying that you can’t get the full functionality of a smartwatch without connecting it to an app. Another says they only discovered after buying their watch that the heart rate monitor automatically switches off while swimming, which they find frustrating and is something worth checking before you buy. 

Which watches do our readers use?

Garmin is the stand-out most popular brand in our survey, used by 78% of users. Apple is a distant second with 15%. Most other brands only got a single mention. A total of 39 different models were listed, showing the wide choice. The Garmin Swim 2 is the most popular watch overall, used by 18% of respondents. However, one respondent said that it hasn’t been updated in six years and surely some innovation is due.

The future of smartwatches

We spoke to several leading smartwatch brands about recent developments in smartwatch technology, and what the future might hold. Darrian Allberry, Head of User Engagement at Coros says there have been big improvements in data analysis. “Algorithmic improvements to analysis functions provide swimmers of all levels with the ability to accurately track training swims and races, and this has made a huge leap recently in overall accuracy.”

Meanwhile, Jasmine Lenthall, a Senior Account Manager at Polar, says “optical heart rate monitoring has been transformative, eliminating the need for a chest strap, which can be challenging while swimming.” She also mentioned stand-alone heart rate sensors, such as Polar’s Verity Sense, that can be worn under your cap or fixed to your goggle strap, as an alternative to wrist-based heart rate monitors. 

Janne Kallio, Digital Ecosystems Lead at Suunto, says their most exciting development is Suunto ZoneSense, which measures athletes’ training intensity using heart rate variability. “Now with ZoneSense, swimmers can evaluate swim sessions to see if it was easy aerobic, over aerobic threshold or even over the anaerobic threshold. This type of intensity analysis hasn’t been available in the past in swimming.”

Additionally, interconnectability between watches and other devices (such as FORM goggles) or data analysis platforms, such as Phlex, now provide swimmers with live feedback and personalised recommendations.

What does the future hold for swimming watches?

As sensor technology gets more advanced it will increase opportunities for tracking how swimmers move through the water, says Kallio at Suunto. Combining this data with AI machine learning could create solutions to help swimmers become more efficient. Improved connectivity with augmented reality goggles could provide real-time guidance to swimmers in the water.

At Polar, Lenthall suggests future innovations will guide swimmers to being more efficient in the water and devices should become ultra-streamlined. The use of AI could help improve personalised recommendations to optimising performance.

Finally, Allberry at Coros suggests that an important future enhancement will be the ability to track fatigue and swimming form over a given session, which could have both performance and safety benefits, especially in open water. AI could be used to analyse your historic data to create personalised training plans.

So which watch should I choose?

Garmin is a popular choice among our readers, and the Garmin Swim 2 was the top choice. However, this model is dated and newer watches provide more data – although one survey respondent noted that a surfeit of data could be confusing. Beyond Garmin, several other brands produce watches with similar capabilities. It’s definitely worth looking around. Take note of the physical characteristics too. Sleek and streamlined will be preferable for swimming but the screen needs to be easy to read under a range of conditions. Check out our review of the best swimming watches for 2024.

Overall, the most important feature swimmers would look for is GPS for distance measurement. Pool metrics came next (distance per stroke, stroke rate etc), closely followed by an inbuilt heart rate monitor – but make sure it works in swimming mode – and a thermometer.

Which watches do brands recommend?

Suunto (Janne Kallio, Digital Ecosystems Lead)

All of our GPS watches can be used for swimming and all provide specific swim features such as pace, distance in the pool, swim stroke efficiency and more. For swimmers, the best watch is therefore often determined by physical characteristics rather than features. For example, the Suunto 9 Peak Pro has a small, sleek design that is great to fit under a wetsuit. The MIP display is excellent in bright, daylight conditions. For pool swimmers, the Suunto Race S is small, lightweight and sleek with a bright Amoled display, and has all the features and data for any swimmer.

Polar (Jasmine Lenthall, Senior Account Manager)

For outdoor swimming, we recommend any watch with GPS capabilities. The Vantage V2, Vantage V3 and our newest Vantage M3 are ideal options, as they offer robust outdoor tracking with accurate distance measurement and additional performance metrics such as heart rate, distance per stroke and stroke rate. For the pool, a number of our watches support swimming metrics including the Vantage, Grit X, Pacer and Ignite series. For swimmers with smaller wrists, we suggest the Ignite 3 or Vantage M3, while those with larger wrists may prefer the Vantage V3. Our latest Amoled displays on these models provide bright, clear visuals, which perform exceptionally well in the pool environment compared to older MIP displays.

Coros (Darian Allberry, Head of User Engagement)

For open water, we recommend the Coros Pace 3. It’s lightweight and low-profile for all day comfort and the battery can last 38 hours on full GPS. For the pool, and for someone who swims indoors and out, we recommend the Coros Pace Pro. All Coros watches automatically detect swimming strokes and count lengths but the Pace Pro has a brighter Amoled screen and integrates ECG for more accurate heart rate data.

Note: We asked Garmin the same questions but they didn’t respond

Find all the gear you need for open water swimming, from adventure bags and swimming togs to tow floats and changing robes, at the Outdoor Swimming Shop. Read more gear reviews. If you buy a product through a link on this page we may receive a commission.

Images: Polar