China Neodymium And Ferrite Magnets Manufacturer & Supplier 
NdFeB magnet is a powerful permanent magnetic material, commonly used in the manufacture of various types of products, the gauss value of the magnet is a measure of the strength of the magnetic field, the gauss value and the distance between the existence of a certain relationship, the following are some basic instructions.
When very close to the surface of a magnet, the magnetic field strength can be very high. For a small magnet (e.g., a round NdFeB magnet with a diameter of 8 mm), the magnetic field strength near the surface can often reach several thousand gauss, e.g., about 3000-4000 gauss.
Related Article: How big is 3000 gauss magnet? How many kg is the pull force?
Radial Cylindrical Perforated Magnets are shown.
As the distance from the surface of the magnet gradually increases, the magnetic field strength sharply decreases. For example, when the distance is 1 time the length of the magnet, the magnetic field strength may decrease to about 1/8 of the surface value. When the distance is twice the length of the magnet, the magnetic field strength will decrease to about 1/27.
Different magnet shapes have different degrees of influence
Such as disc or cylindrical magnets, their magnetic field strength is stronger near the center of the magnet, and decreases faster as the distance increases. Ring magnets due to its open structure, the magnetic field distribution is more uniform, the magnetic field strength is relatively within a certain range of slower decline.
In general, there is a relationship between the Gauss value of a NdFeB magnet and distance. The closer you are to the magnet, the higher the Gauss value and the stronger the magnetic field. If you need a more accurate Gauss value, you usually need to use a professional Gauss meter to measure it.
Maybe you'll like;