You are using an outdated browser. Please upgrade your browser to improve your experience.


Paste this code into your website: Customize


Concerned about magnetic fields in your home? Detect and measure them with this easy to read app scientifically designed for your device! This is an easy to use app to detect and measure 50Hz/60Hz alternating magnetic fields that could be present in your home generated by things like microwaves, hairdryers, electric space heaters, video game consoles, AC/DC power adapters and overhead power lines.

WHAT MAKES THIS APP DIFFERENT? Static or constant magnetic fields like the Earth's magnetic field are less of a health concern than alternating magnetic fields. This app was designed to detect and measure alternating magnetic fields most commonly found in living spaces. These magnetic fields can be generated by electrical devices running on your home mains AC electricity. These alternating magnetic fields have a frequency of 50 or 60 Hz depending on your country.

Studies of the health impacts of alternating magnetic fields as publicized by the International Agency for Research on Cancer (IARC), the World Health Organization (WHO), and by the International Commission on Non-Ionizing Radiation Protection (ICNIRP) has raised the awareness of alternating magnetic fields and generated interest in measurements of them in public and living spaces.

The alternating magnetic fields you may encounter in your home can vary tremendously in strength depending on the device and your distance from it. This app measures the 50 or 60 Hz component of any alternating magnetic field with your device if equipped with a magnetometer. The detection and measurement of alternating magnetic fields is achieved by analyzing functuations in the magnetic field measured by the magnetometer in your device. Normally the magnetometer is used for measuring constant magnetic fields, for example in a compass application. In the presence of a sufficiently strong 50/60 Hz alternating magnetic field the magnetometer measurements fluctuates with time. These fluctuations can be detected and measured by a Fast Fourier Transform analysis. This proven scientific method is able to achieve a sensitivity down to about 0.1 micro-Tesla, much smaller than the Earth's magnetic field of about 40-60 micro-Tesla!

The calibration of several different devices running this app was cross checked with a separate sensor that was tested using NIST traceable methods and instruments. The accuracy of these devices was found to be as good as 20%, however because the location of the magnetometer in each device is not known precisely the measurement you obtain may have a larger uncertainty like 50%.

The main use for this app is to detect and measure 50/60 Hz alternating magnetic fields in public and living spaces. However this app is not a substitute for a professional magnetic field measuring device, and is for private or entertainment purposes only.

This app does not work on an iPod or any device that does not have a magnetometer that is normally used for a compass application. The Watch App works on a Series 5+ and SE. Magnetometers in different devices operating under different conditions can produce poor quality input to this app, affecting the measurement accuracy.

Please respect your device warranty, including operating it within Apple’s published guidelines.

Apple, the Apple logo, iPod, iPhone, and iPad are trademarks of Apple Inc., registered in the U.S. and other countries. App Store is a service mark of Apple Inc.