Our Lowest Price Ever

WORLD'S FIRST SMART HEART MONITOR

  • 24/7 Continuous ECG for comprehensive heart health insights.
  • Monitor Heart Health, HRV, Strain, Heart Rate, Calories, Stress, Body Shock, etc.
Frontier X2
Frontier X2
Frontier X2
Frontier X2
Frontier X2
Frontier X2
Frontier X2
Frontier X2
Frontier X2
Frontier X2
Frontier X2
Frontier X2

Free shipping

Klarna available

14 day risk-free trial

24/7 customer support

Our Lowest Price Ever

WORLD'S FIRST SMART HEART MONITOR

  • 24/7 Continuous ECG for comprehensive heart health insights.
  • Monitor Heart Health, HRV, Strain, Heart Rate, Calories, Stress, Body Shock, etc.

Continuous ECG

Heart Rate Variability

Strain Monitoring

Vibration Alerts

  • Realtime Vibration Alerts to avoid overstraining yourself.
  • Share Live ECG & generate PDF reports.
  • Compatible with Apple, Garmin, Zwift, Peloton, Wahoo and others via BLE.
Regular price£449
/

Free shipping

Easy EMI with Klarna

Risk - free trial

24 / 7 support

There’s a reason cardiologists rely on 24 hr ECG readings. Unlike SmartWatches, SmartRings & other HRMs, Frontier X2 provides Continuous ECG with realtime heart health feedback even during exercise, ensuring high signal quality with comprehensive heart health monitoring during any activity.

  • Frontier Premium Subscription: For the most accurate VO2 Max outside a lab, Zone 2 training with VT1, VT2 Zones, Readiness Score, Oxygen Uptake, and Sleep Stage Analysis.
  • HRM Sports Bra: Features integrated electrodes for external heart rate monitors like Garmin, Polar H7, Frontier X2, and more. Moisture-wicking, high-performance fabric, and standard snap compatibility (45mm distance between snaps).

With Frontier X2, you’ll receive

  • 1 Free consultation with our expert
  • Lifetime customer support
  • 1 yr warranty for added peace of mind

Yes, we offer a 14 Day Risk-Free Trial. So if there is any issue with the product you can Return or Exchange within 14 days.

  • Buy now & pay with Klarna at your own pace.
  • Select the Klarna option at checkout -> Select Payment Plan -> Complete Payment
  • Delivery Partners :

  • Delivery in 3-5 business days (UK )

  • Delivery in 4-7 business days (European Region)

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Go Beyond Heart Rate Monitors & Smartwatches

The Frontier X2 uses revolutionary ECG technology to track every aspect of your heart.

Frontier X2

Heart Rate Monitors

Smart Watches

Go Beyond Heart Rate Monitors & Smartwatches

The Frontier X2 uses revolutionary ECG technology to track every aspect of your heart.

Why we measure from your chest - not your wrist or fingers

ECG watches and handheld devices can only capture your ECG when you are still for 30 seconds.

The Frontier X2 captures high-quality continuous ECG on your chest while you are exercising, sleeping or at rest.

Fits Right Into Your Ecosystem

The frontier X2 measure what matters

Heart Rate

Strain

Real time alerts

Continuous ECG

ECG During Exercise

Superior battery life

Lightweight & durable

One button, all actions

Waterproof up to 1.5m

Try it for 14 days, risk free

Frontier X2 comes with a 14-day, risk-free money back guarantee and 1-year warranty.

Buy Now

High Quality ECG

Continuous ECG up to 24 hours

The world's first and only consumer wearable that allows you to record high-quality ECG in real-time for up to 24hrs during any activity.

Real time, live ECG streaming

Share your Live ECG in real-time with experts, family, or friends, whenever you want, wherever you want, even while exercising!

Detailed ECG graphs

The Frontier X2’s patented ECG technology gives you the unique ability to record up to 24 hours of highly detailed, accurate data through any activity of your choice!

Route maps with ECG

Correlate your ECG data with your GPS data to gain unprecedented insights into your ECG response to pace, elevation, intensity and distance.

Heart Health Metrics

Accurate Chest-Based Heart Rate

Track accurate chest-based Heart Rate through sleep, rest or exercise and get detailed post-activity insights.

Heart Rate Variability (HRV)

Get insights into how your body manages stress and recovery and by measuing your HRV before and after workouts.

Stay Safe with Strain monitoring

‘Strain’ measures the amount of oxygen deprivation experienced by your heart. Manage training intensity to avoid high strain on your heart for prolonged periods.

Rhythm Chart

Get a rhythm chart identifying deviations from the norm, with data explaining the duration, frequency, and occasions when these rhythms occurred.

Heart Health Insights

Activity Tagging & Health Entries

Frontier X2 allows you to capture key events, feelings, or choices in your day to help better understand the response of your heart health to those aspects.

Heart Rate Zone Training

Training in different Heart Rate Zones achieves different goals. Frontier X2 ensures you stay within your chosen zone so your goals are achieved most efficiently.

Monitor progress over time

Analyse the daily, weekly, and monthly progression of all key heart metrics including Heart Rate, Breathing Rate, Strain, and HRV.

Detailed physiological graphs

Use our dynamic web dashboard to view detailed graphic representations of all the physiological metrics measured by the Frontier X2.

Heart Rate Zone Insights

Use our dynamic web dashboard to view detailed graphic representations of all the physiological metrics measured by the Frontier X2.

AI-generated recommendations

Push yourself safely with personalized workout insights and AI-generated recommendations for future workouts.

Exercise and Training

Monitor 20 types of activities

Track and analyse 20 different types of activities, including running, cycling, meditation, sleep, rest, swimming, trekking etc

Effortless zone based training

Set real-time vibration alerts for a range of metrics so you stay within the right workout zone without needing to look at your phone or smartwatch.

Train without distraction

Use the Frontier X2 without connecting it to the mobile app. Review all your physiological metrics without repeated glances at your phone or smartwatch.

Real-time vibration alerts

Train with confidence knowing your heart is protected. Set custom alerts to give you real time feedback when you’re overstraining yourself.

Light, sturdy and durable

The Frontier X2 is so light that you’ll barely feel it on you, but also so durable that no activity is off limits!

Waterproof

The Frontier X2 is IP67 rated - waterproof and sweatproof up to 1.5 meters. Perfect for swimming!

Performance Insights

Sustainable Training with Training Load

Get a true estimate of total exertion during any activity. Weekly Training Load goals help ensure you’re improving your performance without over-training.

Prevent injury by monitoring Body Shock

Monitor your Body Shock to analyse the impact of running surfaces, gear, form changes or fatigue, helping prevent injuries during high impact activities.

Step Cadence

Measure the number of steps taken per minute while running to get additional insights into your running, walking or hiking performance.

Compatibility

Bluetooth 5.0 connectivity

Sync with external devices (Apple Watch, Garmin, Peloton, Zwift, Google Fit, Strava, Wahoo , Training Peaks and other HRM devices via Bluetooth Low Energy.

Integrate with your favorite Apps

Connect the Frontier X2 to external apps in your exercise ecosystem, including Apple Health, Google Fit, Garmin, Wahoo and Strava.

Sync your data across apps

Automatically sync your health and workout data from your favorite apps through Apple Health, Google Fit, Garmin, Wahoo and Strava.

Simultaneous multi-device connectivity

Now connect the Frontier X2 to 3 devices at the same time as an HRM.

Share your data

Securely share your data

Instantly share Frontier X2 data using a secure link so your doctor, family, or friends can stay worry free, always!

Unlimited, unrestricted downloads

Download a .FIT file of your activity summary to upload on to other platforms like Strava.

On-device memory of 24 hours

Frontier X2's on-device memory can store ECG recordings for up to 24 continuous hours, making it perfect for constant monitoring.

Unlimited cloud storage

Get unlimited storage in your own free cloud account. Get lifetime access to 1000s of hours of ECG recordings and analysis.

Share PDF reports

Download a .PDF file of your continuous ECG to either analyse yourself, or easily share with an expert.

Onboarding and Support

Get a Free Demo

Get a Free Virtual Demo upon purchasing the Frontier X2 to learn all about the device and its variety of features.

Complimentary consultation

Receive personalised insights on your training and heart health from a heart health coach who will review your Frontier X2 data and provide personalised guidance.

Lifetime 24x7 support

24x7 support available via email (support@fourtfrontier.com), live chat on our website or mobile app, or by dialling in to our toll free number.

Engage with our community

Engage with thousands of our community members, sharing stories, workouts, and recommendations in your journey towards better heart health.

Quick and easy onboarding

Get in-app onboarding and an easy to use knowledge base to get familiar and comfortable with all of the Frontier X2 features.

Quick Start User manual

Download a PDF version of the user manual by clicking here, if the step-by-step online manual isn't for you.

Device Specs

METRICS
  • Heart: Heart Rate, Strain, HRV (Heart Rate Variability)
  • Performance: Breathing Rate, Training Load, Body Shock, Step Cadence
Device size
  • Weight: 25 grams
  • Dimensions: 73mm x 24mm x 13mm
  • Water resistant up to 1.5 meters
Battery
  • Upto 24 hours of continuous usage; 12 - 15 days under typical usage
  • Full charge in under 45 minutes
CONNECTIVITY
  • Frontier X2 now has Bluetooth 5.0 for 3X speed and greater range.
  • Frontier X App available for iOS and Android phones, as well as the Apple Watch
  • Displays Heart Rate on compatible BLE sports watches
In the box
  • Frontier X2, Elastic Chest Strap, Micro USB Cable, Quick Start Guide

Spotlight Stories

Inspiring heart health journeys shared by our community members.

Frontier X2 Certification

Frontier X2 is manufactured in accordance with the highest international standards. Frontier X2 comes with 10+ device certifications along with the IP67 rating - waterproof and sweatproof up to 1.5 meters.

FAQs

The Frontier X2 is the World’s First Smart Heart Monitor that allows you to record your ECG during exercise.

Unlike a regular heart rate monitor, which typically only transmits heart rate, the Frontier X2 records, stores, and processes your ECG (during both exercise and rest), Heart Rate, Strain, Breathing Rate, as well as biomechanical parameters like Cadence (step rate) and Body Shock.

The Frontier X2 can also give you real-time feedback through vibration alerts, when you cross preset thresholds for Heart Rate, Breathing Rate and Strain. Moreover, you can transmit the physiological metrics recorded on the Frontier X2 to anyone across the world, in real-time. This includes the ability to live-stream your ECG in real-time to anyone at anytime as well.

Most devices on the market that allow you to record ECG are either watches or hand-held. Hand-held and Watch ECGs require you to sit still and hold the device with both hands, so they cannot be used during exercise. They also suffer from poor data quality, because the ECG is being acquired from the finger or wrist, instead of the chest. Further, they typically record only 30-60 second segments of ECG and do not allow for long continuous recordings like the Frontier X2.

With the ability to record up to 24hrs of continuous ECG data, the Frontier X2 was designed to get the best quality metrics while on the move, in any environment. The chest-worn design keeps your hands free for sport and is tightly fastened to ensure good data quality during motion. By collecting the ECG from the skin just over the heart, the Frontier X2 can pick up minute electrical changes that may be lost if the ECG is picked up from points further away, like the arm, wrist or fingertips. The ECG quality on the X2 has been validated against a GE Holter Monitor and most closely resembles the V5 lead position of a 12-Lead ECG.

The Frontier X2 measures changes in your ECG, indicating oxygen deprivation and heart muscle damage. The device subsequently provides your Strain values in real-time on our app. It also warns you with a double-vibration alert if you cross your pre-set threshold, helping you exercise at an exercise intensity that is safe for your heart. This alert can tell you whether you should finish the last lap, run that extra mile, do those last few push ups, or just give your heart a rest.

The Frontier X2 measures both Breathing Rate and Heart Rate. Breathing rate is much more closely correlated with your true internal effort than Heart Rate, because unlike Heart Rate, it is not influenced by external factors like caffeine, lack of sleep, temperature, humidity and stress, which are some of the problems with Heart Rate based training. The Breathing Rate based alerts on the Frontier X2 tell you when to speed up and when to slow down, enabling you to optimize your performance.

The ECG obtained from the Frontier X2 resembles the V5 lead position of a 12-Lead ECG. The quality of the ECG has been validated against a GE Holter Monitor.

Please note the Frontier X2 is a health & fitness product, and is not intended to be used for diagnostic or treatment purposes. Please read our detailed disclaimers here.

​The Frontier X2 uses Bluetooth Low Energy (BLE) Technology/Bluetooth Smart to sync with other devices as a heart rate monitor. These devices include certain models of ​Apple Watches, Garmins, Whoop Straps, Pelotons and more. If your external device is equipped with BLE/Bluetooth Smart technology, the Frontier X2 should easily sync as a heart rate monitor (HRM) with no issues whatsoever. 

The Frontier X2 can simultaneously connect to a maximum of 3 devices - 1 Mobile App & 2 External HRMs.

While the external device will only reflect Heart Rate, the Frontier X2 itself will reflect various metrics such as ECG (live and recorded), Breathing Rate, Strain, Heart Rate, Body Shock, and Training Load once it is connected to the mobile app, post your workout. You can see a more detailed view on the Frontier X web dashboard as well, once you've uploaded data from your device to the cloud.

Please note that the Frontier X2 does not support ANT+

There is currently no direct integration between the Frontier X2 and these fitness apps. However, there are a couple of workarounds.

When the Frontier X2 is connected to your phone/apple watch app and the phone/watch is carried along - it allows you to record GPS data as part of your workouts as well. The Frontier X2 doesn't have a GPS chip of its own, and thus uses the phone's/watch's GPS. You can then download a .FIT file of your workout from the Frontier X2 dashboard and upload it to apps like Strava, Training Peaks, JeFit etc. for further analysis. 

Alternatively, you can connect the Frontier X2 to an external HRM like a Garmin or Polar and then pass the information on to Strava or Training Peaks from your external HRM. The data uploaded onto Strava in this case will include the Heart Rate measured by the Frontier X2.

A fully charged Frontier X2 can last for up to 24 hours when recording data continuously and 14 days if used for an average of 1 hr/day.

Yes. You can record data on the Frontier X2 without connecting the device to the mobile app. The Frontier X2 is equipped with a memory chip, unlike most other devices on the market. This ensures that even if you don't connect it to your phone during your workout, or choose to connect it to an external device like Garmin, there's zero data loss as you can come back home and connect the Frontier X2 to the phone later. Once synced, all metrics recorded on the device will be accessible.

Swimming is one of the most common use cases of the Frontier X2. The Frontier X2 is IP67 rated, which means that it is completely waterproof for up to 1.5 meters (approx. 5 ft).

Yes. The chest-worn design of the Frontier X2 keeps your hands free for sport and is tightly fastened to ensure good data quality during motion.

While Frontier X2 has not gone through the official safety testing for use with pacemakers, we have several users who use the device with pacemakers. None of these users have reported any issues.

The Premium Subscription provides access to advanced heart health metrics, including VO2 Max, Ventilatory Thresholds, Readiness Scores, and Sleep Stage Analysis

By subscribing to our Premium plan, you unlock a suite of powerful features that enhance your monitoring capabilities. This includes the most accurate VO2 max readings outside the lab and the most precise readiness score available.

The Premium Subscription offers great value at £109.99 per year or £13.99 per month*, giving you access to advanced features and personalized insights to support your heart health journey.

Yes, you can cancel your Premium Subscription at any time. We believe in flexibility, so you’re free to adjust your subscription based on your needs without any cancellation fees.

The metrics and insights are updated in real time, allowing you to monitor your progress continuously. You'll receive regular notifications and reports that reflect your latest data, ensuring you're always informed about your heart health and fitness levels.

The Premium Subscription is exclusively designed for use with the Frontier X2. It is tailored to enhance the unique features and functionalities of this device, ensuring optimal heart health monitoring and insights.

Customer Reviews

Based on 443 reviews
77%
(341)
10%
(44)
4%
(17)
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(16)
6%
(25)
A
Anthony
For those of us who are aging-athletes

For those of us who are aging-athletes with many decades of ultra-endurance training and competition and consequent cardiovascular issues, the metrics FF X2 provides are indispensable to be able to see in real-time. For me, those data, when combined with real-time measurement of muscle oxygen and watt output allow me to calibrate my work to enhance safety and fitness. To my knowledge, there are no other wearable monitors at the price point of the X2 and Premium subscription that can provide such data.

B
Brad
Fourth Frontier X2 is helping me manage heart issues

Quick background--I had been having some irregular heart beats during exercise and was looking for a way to investigate what was going on. Found the Fourth Frontier X2 online. I use it every time I workout now and also when I sleep. I have gotten a lot of great insight into my heart health and am quite happy with the product. The X2 is helping me and my doctor manage my newly diagnosed Atrial Fibrillation.
--The Heart Strain indicator is quite helpful. I have had the "buzz" on the device go off a couple of times. It tells me to lower my workout intensity.
--The heart rate is accurate--as compared with my Polar H10 strap and several manual counts. --Breath rate is helpful information not supplied by other heart rate devices --The HRV reading is helpful and compares very close to my Oura ring. --Sleep data is impressive and compares very close to the Oura ring. --The X2 could easily take the place of the Polar H10 strap and Oura ring. --The App is intuitive and provides a lot of useful information. --I love that the app will generate a PDF of the ECG that can be emailed to your cardiologist/doctor. --I love that the X2 is charged via USB instead of a battery like the H10. --Battery life is impressive--I have worn it all night while sleeping followed by 3 hours of use during exercise and have not gone below 70% charge. I once wore it for 18 hours and only got to 60% charge. The X2 charges in just a few minutes-much faster than my Apple watch. --My cardiologist was enthusiastic about my use of the X2. He found the ECG data useful--especially because he could see what was happening during a specific activity. I had worn a 2 week monitor through him--but of course I didn't have any weird beats until after I turned in his device. The X2 ECG is helping to guide my treatment.

H
Holly Klingler
Offers unique/valuable health insights most devices can't and excellent service

If you want to really learn about your heart health and what impact it, this is the device. Ive used many health devices, and they all more or less give you the same data. While that data is informative, I wanted deeper insights into my heart health and Fourth Frontier does this better than any device I know. Yes, its on the pricier side and I was reluctant about that, but the great thing is that you can get a full, one-on-one demo. I talked with Vijay Kumar who took the time to walk me through what it does, answered all my questions, and made sure the device is a fit for my needs. I was looking for a device that would give me all-day readings, and he showed me exactly how it could do just that. So, the purchase was seamless. I never felt rushed or pressured. The device itself far outdid my expectations. I was nervous about whether the battery would give all-day readings, and it does. The readings give me much better insights into my heart function than any device Ive tried. Whats even better is that you get a consultation with a real healthcare professional who helps you understand your readings. I learned more in that session than months and years of data from other sources and/or doctor visits. Both the mobile device and the desktop dashboard give you a lot of insights. Finally, in just the few months Ive owned this device, they have updated and added features and services so that the device and the information continue to improve. As someone who loves to try out new tech and learn about my health through insights, Im super impressed!

J
John Pike
Frontier X2 - an excellent heart monitor -

I've had lots of exercise monitors over the years but was looking for one with multiple and extensive features. The Fourth Frontier X2 is an excellent monitor providing me with all the stats I'm interested in for a heart monitor...as well as special features such as an indication of VO2 Max (with the premium membership). Also, customer service has been excellent vie email whenever I've had a question.

B
Bruce Bosland
The Frontier X is an excellent product

The Frontier X is an excellent product, backed by a team that listens to its customers and responds promptlya refreshing approach in todays market. It may be the best heart rate monitor for fitness enthusiasts.