Innovative vital sign monitoring

Leading technology in mobile vital sign monitoring


In-Ear Mobile Measurement

The cosinuss° One is an In-Ear Wearable that monitors your heart rate precisely.
Additionally it measures your heart rate variability and your body temperature.
Blood Oxygen level will be coming soon.

The °One is the smallest and lightest heart rate monitor worldwide. It weighs only 6 gramms and
has an overall size of about 4 x 4 centimeter. For the first time the optical heart rate measurement
has become as precise as the electrical one. All devices that feature either Bluetooth or ANT+ are
able to connect to the °One.

  • Pleasant to wear
  • Precise measurement
  • Compatible with sports watches, bike computers and fitness apps.

Anja Beranek, our brand ambassador, is one of the most charming pofessional triathletes.
She loves measuring her heart rate without a chest strap using the cosinuss° One.

cosinuss° One

cosinuss° One

Strapless heart rate & heart rate variability.

Continuous body temperature monitoring.

That´s the new cosinuss° One!


Plug & Go



Light weight, left or right ear - exactly how you like it.



Thanks to earconnectTM and circummission method.



With any sports watch, bike computer or app.



The patented earconnectTM Technology is combining medical technology together with sport science. This is how we are bringing optical heart rate monitoring to a level of perfection.

Become a forerunner to innovative vitalsigns detection now.



Bluetooth low energy and ANT+ standard connections makes your °One able to connect with every device that features heart rate reading, such as sportswatches, bike computers or fitness-apps.

Upgrade your equipment with a pleasant and precise heart rate sensor.

Jan Frodeno und cosinuss°
Jan Frodeno, der Ironman Weltmeister, misst seinen Puls im Ohr - ohne Brustgurt.

Jan Frodeno, Ironman World Champion, measuring his heart rate without any cheststrap - simply in ear.

Jan Frodeno, Ironman World Champion and Olympic Triathlon Champion.

"I am measuring my heart rate and even body temperature without being cramped by a cheststrap"

Everybody who is doing sports to achieve a certain goal, has to know his own limits - and then challenge them. No matter if you just want to make a certain pace or place or just burn calories.

My personal interest about cosinuss° comes with the ability of a mobil and continuous measurement of my body temperature during my training sessions. A big Bonus to that is of course the heart rate monitoring without that heck of cheststrap. Finally i am feeling free again breathing fresh air.

cosinuss App
Regelmäßige Updates für deinen Pulsmesser


Updates on a regular basis will keep your °One running at the forefront of cutting edge technology. Over-the-Air Transmissions will upload the latest updates to your sensor automatically as soon as it is connected to the cosinuss° app.

You can download our homemade cosinuss° One App for free and without any registration. It is available in the Google Play Store or in the App Store.

Beobachte den richtigen Sitz und die Messung des Puls-Sensors im Ohr

Quality of measurement

In the cosinuss One App you can easily check the quality of your measurement, which is depending on the positioning of the sensor in your ear canal. Check it simply by watching the receiving beam. If the indication is good to go, then so are you.

Inside the app you can additionally monitor your body temperature as well as the battery life of your sensor all the time.

Graphische Auswertungen deiner Daten erleichtern dir dein Herzfrequenztraining


The most important Data is shown to you in a clean and simple way. So you don´t get confused over numbers during your training sessions. Take a look at your training quality by comparing sessions in the history or live mode.

Do a CSV-Export of your sessions to analyze or archieve them on your computer. Or even create your own application with your very own data.




You got any questions? We are here to answer them? We can give you recommendations to your chosen size, helpful hints for your daily use and of course technical support with connecting issues or anything else.
Just get in contact with using our website form. We are happy to receive your feedback.



Our goal is called: The Optimum. Therefore we offer you a free exchange of your sensor in case that you are not confident with it, or if you just want to switch sizes. We are constantly developing our technology to get the best out of it, just as you do. So be with us.

About us


Cosinuss ia a young technology firm based in munich. We are engineering wearable technology, sensors and algorythms to measure vital signs in more smart and comfortable way. Our products already find use in fields of professional Sports, Health and Medicine and occupational health and safety

Made in Europe


The cosinuss° One is developed in munich, where we are engineering and testing it. Our small team is taking care of you and your °One. Cosinuss is only producing inside of europe in countries like Hungary, Spain and the Czech Republik.


Android App Update

Here is the what's new that was added to Google Play:

  • German support
  • Your training session can be shared on your Facebook timeline
  • Device firmware update improved
  • The Bluetooth scanner to connect to your °One lasts longer and can be
    started from the main screen by pressing the sensor icon.

Update iOS & Android März 2016

New features for iOS;

  • The sensor's firmware is able to be updated
  • The sensor pairing feature has been improved
  • The values on the main screen can be highlighted by touching them
  • A running session can be paused and resumed
  • Activities can be created, edited, deleted and attached to a session
  • The heart rate and temperature data can be visualized in a chart (from the history)

The main visible change for the Android User is the signal quality feedback.