Description
Frequently Asked Questions
How does Swimtraxx One attach to my goggles?
Swimtraxx One clicks onto the strap of your swimming goggles. Place it on the right side — this is essential for the algorithm to work correctly. It fits most standard goggles, no special equipment needed. For goggles with extended visors (e.g. Arena Cobra) where the sensor can’t make skin contact, you can also wear it under your swim cap.
How accurate is the heart rate measurement?
The optical heart rate sensor sits at the right temple, which is one of the most reliable locations for underwater optical HR measurement. Skin contact between the sensor and your temple is required for accurate readings. This head-mounted position outperforms wrist-based sensors that struggle with water flow interference during swimming.
What metrics does it track?
In the pool (9 parameters): heart rate, lap time, stroke type (auto-detected: fly, back, breast, free), stroke rate, stroke count, breath count, turn time, underwater time, and stroke length.
In open water (5 parameters): heart rate, stroke rate, stroke count, stroke type, and breath count.
Is there a subscription fee?
No. Swimtraxx One is a one-time purchase. The Swimtraxx Hub app and all features are included free — no monthly fees, no premium tiers, no hidden costs. Ever.
Can my coach see my data live?
Yes. The Swimtraxx Hub app connects wirelessly to multiple Swimtraxx One devices simultaneously. Coaches see live heart rate, pace, stroke data, and more for every swimmer in the water, right on their iPad at the pool deck.
How long does the battery last?
Up to 8 hours of continuous tracking. Charging takes about 2 hours via the magnetic charging cable.
Will I feel it while swimming?
At 12.7 grams, swimmers consistently report forgetting it’s there after the first few laps. It was co-developed with Olympic-level swimmers including Femke Heemskerk and Pieter Timmers to ensure zero interference with technique and hydrodynamics.
Can I use it in races?
Yes. Swimtraxx One is World Aquatics approved for racing under Rule SW 15.3 — the first and only platform to provide comprehensive swim tracking capability in-race.
Does it work in open water?
Swimtraxx One can be worn in open water and will track heart rate, stroke type, stroke rate, stroke count, and breath count. However, without pool walls there is no lap detection — your swim is recorded as one continuous lap. There is no GPS, so distance cannot be tracked outdoors. Swimtraxx One is designed primarily for pool swimming.
What happens to my data?
Your data syncs to the Swimtraxx Hub app after each session. You own your data. Review detailed analytics, track progress over time, share automatically with your coach, or sync to Strava.
Free Worldwide Shipping
Delivered to your door at no extra cost, wherever you are.
2-Year Warranty
Built to last. Full manufacturer warranty on every device.
No Subscription
One purchase, full access. App and all features included free forever.






Customer –
Perfect
Small, compact and does what it should.
Karl –
Compact and wearable
I no longer need to wear a watch and still get more data. Permanently attached to my goggles. Easy.
Maaike –
Great support
I use it during every swim after support walked me through setting up Swimtraxx One on my phone.
Johan –
Works nice!
I tried Swimtraxx the same day I recieved it, worked nice and got data into the ipad on the pool deck where my friend watched as I did some laps, some sprints and a little bit of drills.
Thomas –
Swimtraxx One keeps getting better!
Swimtraxx One is an exceptional swimming tracker that continuously evolves with each update. The team's unwavering dedication to improvement shines through in its remarkable accuracy and user-friendly applications. For swimmers seeking enhanced performance and reaching new heights, I truly recommend
Markus B. –
Best solution
Swimtraxx is accurate and reliable and is more accurate and reliable than what we used before. Overall, Swimtraxx is more intuitive and easy to setup and the live feedback on pool deck during training by Swimtraxx is very helpful
Brice-Henri T. –
Accuracy
Swimtraxx is very accurate when we are swimming. However, it is completely lost when we are doing drills. So the data are not correct as mentioned on the website. However, I was expecting maybe a possibility to update the workout manually and add those drills but it is not possible apparently.