Convert magnetic field strength H between ampere per metre, kiloampere per metre, and oersted, then compare SI and CGS expressions side by side.
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Magnetism Units
A magnetic field strength converter helps when magnetics references switch between SI ampere-per-metre notation and older oersted notation. This page keeps the job narrow and honest: it converts field strength H only, without pretending that field strength, magnetic flux, and magnetic flux density are interchangeable.
Magnetic field strength H describes the magnetizing force applied by a current or magnetic circuit. It is not the same quantity as magnetic flux density B, even though the two are closely related in electromagnetism.
That distinction matters because the relationship between H and B depends on permeability. A converter for H should therefore stay within field-strength units instead of silently assuming a material or vacuum condition.
Modern SI work reports magnetic field strength in ampere per metre, often scaled to kA/m for larger values. Older references, magnetics handbooks, and some legacy component notes still use oersted from the CGS family.
A clean converter helps you cross-check those documents without manually carrying the 4π relationship every time you switch notation.
1 Oe = 1000 / (4π) A/m ≈ 79.5775 A/m
Core SI-to-CGS relationship used to compare oersted with ampere per metre.
1 kA/m = 1000 A/m
Shows the SI scaling step between kiloampere per metre and the base unit.
Use a magnetic flux density converter when the quantity is B and the source uses tesla or gauss. Use a magnetic flux converter when the quantity is total flux in weber or maxwell.
Keeping those pages separate prevents a common mistake: treating field-strength notation as if it were automatically a material-independent magnetic result.
Frequently asked questions
No. Magnetic field strength H and magnetic flux density B are different quantities. Their relationship depends on permeability, so a unit converter for H should not silently substitute B units.
Because legacy CGS-based magnetics literature, older component notes, and some historical engineering references still use oersted. A converter remains useful when reading across SI and older notation systems.
Use kA/m when the A/m value becomes large enough that the prefixed form is easier to scan and compare. The underlying field strength does not change; only the reporting scale does.
No. That step needs additional physics context such as permeability and geometry. This page converts only magnetic field strength units themselves.
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