The new digital teslameter system (also called Gaussmeter) incorporates a novel, very small 3-axis Hall probe, analog electronics based on the spinning-current technique, analog-to-digital converter, computer, and display. The Hall probe is a single silicon chip with monolithically integrated horizontal and vertical Hall magnetic sensors and a temperature sensor. The spinning-current eliminates most of the Hall probe offset, low-frequency noise, and the planar Hall voltage. The errors due to the Hall element non-linearity and the variations in the probe electronics temperatures as well as the errors due to the angular errors of the Hall probe are eliminated by various calibration procedures. These new developments resulted in a teslameter that can measure magnetic field vectors from about 1µT to 30T, with the spatial resolution 100 µm, magnetic resolution ±2ppm of the range, the accuracy ±0.0001% of reading + 0.001% of range, temperature coefficient less than 5ppm/°C, and angular errors less than 0.1 degree.