It all starts with data

ACT Head Impact Tracker is measuring device for impacts and forces acting on a head while doing sports.

Use ACT Head Impact Tracker to:

1. Make forces acting on a head visible and more tangible.
2. Get objective information on what happens and make better informed decisions.
3. Create, enforce and track compliancy to restrictions, actions, practices, procedures and protocols.
4. Reinvent technique training: lower the magnitude to make them brain healthier and safer.
5. Improve awareness and understanding of head impacts and forces acting on a head, advocate the change in attitudes and behavior.

ACT Head Impact Tracker head sensor
ACT Head Impact Tracker head sensor Pro

ACT Head Impact Tracker head sensor is an integral part of ACT Head Impact Tracker, it is what measures forces acting on your head. There are two types of head sensors:

ACT Head Impact Tracker head sensor measures number, frequency and proximity of impacts and forces acting on a head. Magnitude measure is g-force (linear acceleration/deceleration) and Impact g-load  (accumulation of g-forces).

ACT Head Impact Tracker head sensor Pro measures number, frequency and proximity of impacts and forces acting on a head. Magnitude measures are g-force (linear acceleration/deceleration), Impact g-load, (accumulation of g-forces), rad/s (angular velocity) and accumulation of angular velocity.

Head sensors can be attached to almost any kind of head a

ccessory or wear: variety of hair bands, head bands and helmets. Choose what to use, or buy one of ACT Head Impact Tracker accessories specifically designed for it in our web store. What ever your head wear, gear or accessory of attachment, ensure the sensor is firmly attached and it can not move or get loose. The head sensor has to stay put and in place to give quality measurement.

Note: head sensor measures what is it attached to. We recommend attaching ACT Head Impact Tracker head sensor to your head with a tight-fitting head accessory (like head band) also when using with a helmet. If you attach sensor on a helmet, the magnitude measurement accuracy might be compromised, the forces acting on a helmet are many cases higher in magnitude to those acting on your head inside the helmet.

ACT Head Impact Tracker smartphone mobile App

ACT Head Impact Tracker smartphone mobile App is needed to operate ACT Head Impact Tracker head sensor(s). App enables you to create and manage User Account and Profile(s), add and act with ACT Head Impact Tracker sensors on your Profile(s), view and receive impact information, review Profile(s)’s impact history, share your Profile(s) Impact information with other Users, activate, use, and manage certain Service features and functionalities. On the sidelines use smartphone App to listen the sensors, send information from the sensors to the cloud (using mobile data or Wi-Fi), get and keep an eye on near-real-time data on the events.


ACT Head Impact Tracker mobile App for Android smartphones
App is free to download in Google Play Store on smart phones with Android 9 or newer operating system.
Please note that all different smart phone brands and models have not been tested, and cannot be granted to work, or work as intended with ACT Head Impact Tracker. Also operating ACT Head Impact Tracker might vary a bit between the brands and models. Check comments made on your Android phone brand and model in this website Help > Before you buy > What smartphone devices are compatible with ACT Head Impact Tracker?

ACT Head Impact Tracker App for iPhones
iOS App is not available yet. Estimated launch in App Store early 2024.

ACT Head Impact Tracker Browser Access

You can access your user account and get all the data in it plus much more in ACT Head Impact Tracker Browser Access. There are two levels in Browser Access: Web User Interface and Team Dashboard.


Team Dashboard

Team Dashboard is statistics and light analytics tool for coaches, trainers, teams and clubs. Its Beta1 pilot test version is now out for all our users to test use. See detailed instructions for use in Help-page 8. Team Dashboard section.


Web User Interface

In web user interface, you get vast number of detailed measurements collected and data it has been converted into both in numerical and graphical illustrations. Much more so than what is featuring in the App.
You can also mark false positive events (like those of transportation, handling and other) as faulty impacts and add notes to events, browse the data on and smartphone, tablet or computer, and import your impact data to most common spreadsheets (such as Excel or Numbers) in Web User Interface.
Access Web User Interface by clicking “Browser Access” (in Users column) in the bottom of this webpage.


Use Browser Access for data crunching!

What makes ACT Head Impact Tracker so unique, and right for you?


ACT Head Impact Tracker head sensor can be used in virtually any sport on a dry land.



ACT Head Impact Tracker head sensor can be attached with hook&loop (Velcro) tape to wide variety of head gear and wear, helmets and head bands. You can also buy ACT Head Impact Tracker accessories in our webstore.


For team sports and individual sports, to track one athlete or a team of athletes, for juniors and seniors, professional and recreational levels, men, women, boys, girls and anything in between.

Easy to use

Download the App, create user account and profile(s), add head sensors to the profile(s) and off you go


Head sensor’s dimensions are: 46,70mm x 34,40mm x 7,60mm


No need for extra gadgets such as large team charging units, dedicated hand held or sideline devices. No monthly fees for services you don’t need or want to use

Why you should measure every day?

Every athlete, coach, trainer, relevant team personnel, and parent can:

1. Track the impacts occurring.
High numerical values indicate more violent impacts.

2. When a high magnitude impact, blow or jolt occurs, act on it.
If no medical professionals are available on site to do the assessment, we recommend using well-established assessment tools, such as Pocket Concussion Recognition Tool 5®.

3. Keep a close eye on the impact history.
When did the previous impact occur? How frequently the impacts occur? How close proximity they come? How many impacts have you had today/this week/this month/…?

4. Make forces acting on a head visible and concrete.
Create awareness and understanding with objective measures. No more guessing and guestimation. Educate when and why they occur and what they may cause. Aim for a good sportsmanship and increased respect, less risk-taking, using excessive force and foul play.

5. Take a stand and send a message.
Measuring the impacts and acting on them, signals to everyone involved that this matter is with very high significance and closely observed. Incidents will not go unnoticed and will be acted upon. No-one should fear for their life, health or well-being when doing sports. You are riding on the 1st wave to make this change.

Every coach, trainer and relevant team personnel can:

6. Track down the athletes with more in number, higher in magnitude, closer in frequency and proximity than their peers.
Address the issue with athletes at risk, decrease the number, magnitude, frequency and proximity of impacts and forces acting on a head.

7. Identify the trainings and drills with most events, large magnitude events or most frequent events on the athletes involved.
Modify them and/or lower their frequency in the training schedule to decrease the load of all the athletes involved.

8. Identify the positions more prone to head impacts and forces acting on a head.
Keep an eye on the players in those positions and modify the training plans to reduce the impact load of the athletes in those positions.

9. Trained eye of a coach may detect technique with need of improvement.
Headings, giving and receiving a tackle for example usually show on the graphical illustrations on the forces. Compare the graphs to detect gaps in techniques.

10. Introduce and apply a suitable sideline procedure.
Demonstrating objectively that impacts are occurring should encourage coaches, trainers and team personnel to introduce and apply suitable sideline procedures.

11. Share with those who care and can help to reduce impact load.
Users can share their impact data with those who should know too. These can be for example parents, coaches, trainers, or co-athletes.

12. Lead the way.
Teams and clubs tracking the head impacts truly aim to do everything they can to monitor athletes on the pitch. Towards safer, healthier and happier sports for everyone.