Magnetizing field converter
Convert magnetic field strength between amperes per meter and oersteds — the field a current makes, before any material responds.
That's 1.99× as strong as the Earth’s field, while a fridge magnet is 50× stronger. In free space that would make about 100 µT.
What it means
How strong is that field?
H and B are only proportional in free space. Inside iron, the same H produces hundreds or thousands of times more B.
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Learn
Three things worth knowing
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1 Oe = 79.58 A/m
The awkward number is 1000/4π, which comes from the CGS system putting a 4π in a different place than SI does.
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Coercivity is quoted in H
A magnet’s resistance to being demagnetized is an H field, in oersteds or kA/m. That is why magnet datasheets carry both a tesla figure and an oersted one.
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Oersteds are not gauss
They are numerically equal in free space, which hides the difference. In a material they are completely different quantities, which is where CGS magnetics catches people out.
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Background
About H and B
There are two magnetic fields, and confusing them is a classic error. H, in amperes per meter, is what the current produces. B, in tesla, is what actually exists once the material has responded.
In air they are proportional — one ampere per meter makes 1.26 microtesla — but inside iron, B can be thousands of times larger for the same H.