A flux Helmholtz coil serves the same purpose as a teslameter in that it can measure the residual magnetic induction of a magnet. However, when measuring a small magnet with a teslameter, the distance between the probe and the sample surface must be accounted for and accurately removed, otherwise there is a large amount of error. The use of a flux Helmholtz coil effectively solves this problem, as the flux Helmholtz coils is used to produce a uniform magnetic field and can also be used for open-circuit sample flux measurements. The magnet being tested is removed from the center of the coil and then the magnetic flux in the Helmholtz coil changes the induced voltage. This change is transmitted to the fluxmeter, which obtains the flux variation through data processing.