The Moodmetric smart ring is a real-time and accurate device for measuring electrodermal activity.

Moodmetric / Technology

Measuring electrodermal activity with the Moodmetric smart ring

The Moodmetric smart ring was developed for measuring electrodermal activity accurately in a convenient, wearable form.

The Moodmetric smart ring is a research device and it was developed to respond to researchers´ needs. The ring form factor assures accuracy.

Using the Moodmetric smart ring is easy and it can be deployed in only a few minutes. The measurement happens in real time and the measurement result is seen on the screen of a smartphone immediately. The stress level fluctuations can be followed in different situations with the app. It shows what increases and decreases stress levels.

The phone does not need to be with you, you can transfer data any time, for example in the mornings and evenings.

The Moodmetric app is clear and robust on both iOS and Android devices. There is no need to login to the app nor transfer data to the internet. There is a possibility to login to the Moodmetric cloud service and upload your personal data, but this is not mandatory. Full benefit of the ring can be achieved also without login.

Electrodermal activity (EDA)

also: galvanic skin response (GSR), skin conductance response (SCR)

The connection between psychological factors and skin conductivity was found almost simultaneously by a French neurologist Féré (1888) and a Russian physician Tarchanoff (1889). The first findings were done already ten years prior by a French therapist Vigouroux.

Electrodermal activity is improved when eccrine sweat glands form sweat on the surface of the skin. Eccrine glands are innervated by the sympathetic nervous system and they are part of the fight or flight response system. This makes electrodermal activity (EDA) important from the stress measurement point of view.

Measurement accuracy

Two recent research studies have examined the quality of the Moodmetric measurement signal. Both studies concluded that the accuracy of the signal produced by the Moodmetric smart ring is very close to that of laboratory devices. (Torniainen et al., 2015; Pakarinen et al., 2019)

When compared to laboratory devices, the signal accuracy of the Moodmetric measurement is 83%. This is a very good result for a research device.

According to these studies, the Moodmetric smart ring is valid for research. It is also a reliable tool for measuring personal well-being.

Read more about the measurement accuracy >>

The Moodmetric series of articles explains in more detail the scientific validation of the methods and tools used, and how the Moodmetric measurement can be applied in, for example, field research.

Frequently asked questions

Technical data

  • The Moodmetric smart ring measures electrodermal activity
  • Includes step counter
  • Battery life is is approx. 1 week
  • Memory size is approx. 12 hours
  • Bluetooth range 5 meters at minimum
  • Data in CSV and Excel formats
  • The ring is not waterproof

Smart wristbands, smart watches and smart rings measure physiological signals. Most of the technology is centered on measuring heart rate or heart rate variability. All the trackers have at least one accelerometer which is used for, for example, counting steps.

The Moodmetric smart ring measures electrodermal activity. It is designed to measure stress levels based on the activation of the sympathetic nervous system. Stress can be triggered both by negative (anxiety, irritation, frustration, fear etc.) and positive (enthusiasm, excitement) emotions and reactions. The Moodmetric smart ring can be used for long-term monitoring, or for the detection of single reactions in real time.

The ring helps the user to understand their psychological (emotional and cognitive) load better. For example, intense emotions and demanding math tasks easily raise stress levels.

The Moodmetric smart ring measures electrodermal activity 24/7. The ring is therefore suitable for measuring stress and recovery both day and night. So, to improve your sleep, the Moodmetric smart ring helps you to analyse what causes stress during the day.

Physical activity or sudden peaks in stress levels do not affect the overall average MM levels. The results can be viewed on the app anytime of the day.

The Moodmetric smart ring measures skin’s electrodermal activity. High Moodmetric levels tell about positive or negative stress and low levels about calmness or tiredness.

Electrodermal activity (EDA) tells about the activation of the sympathetic nervous system. Other terms used are galvanic skin response (GSR) and skin conductance (SC).

The Moodmetric smart ring measures electrodermal activity with an accuracy of a laboratory device. The Moodmetric algorithm computes an easy to interpret index on a scale of 1-100.

The Moodmetric index is robust to motion. The index is comparable among users.

The Moodmetric smart ring is not only a tool suitable for personal stress management, but appropriate for field research too.

Measuring skin conductivity requires a high density of so-called eccrine sweat glands. For this reason and for the most accurate results, measuring has to happen on the palm of a hand, finger, or sole of a foot.

The measurement accuracy is optimal when measured with a ring.

Data protection

Who has access to the measurement data?

The Moodmetric measurement data is on the user´s phone, not accessible to others.

What if I want to use the Moodmetric cloud service?

Moodmetric does not collect and store unnecessary data of the users of the Moodmetric smart ring. Signing up to the Moodmetric cloud is voluntary and requires only name and email address. The only data stored from the phone to the Moodmetric cloud is the Moodmetric Measurement data; no other information from the Moodmetric app or the user´s phone is transferred to the cloud.

Read more about data privacy of our website and the Moodmetric cloud service: Privacy Policy.