Popular conversions
1 pairsAmpere per Meter ↔ Oersted
A/m ↔ Oe
Unit guides
2 unitsDetailed guide to this category
Magnetic field strength expresses the magnetizing force generated by a current relative to length.
Ampere per meter is the SI derived unit, while oersted remains common in the magnetic materials industry.
- Physical quantity
- Magnetic field strength
- SI unit
- Ampere per meter
- Typical use
- Electromagnetic field and coil design
What is magnetic field strength?
Magnetic field strength measures the magnetizing force in a region, derived from current and length.
It is used in coil, electromagnet and magnetic material engineering.
Magnetic field strength and flux density
Magnetic field strength is expressed in amperes per meter, while magnetic flux density is commonly expressed in tesla. They are related but describe different quantities, so do not substitute one for the other without the material relationship that connects them.
Field-strength units appear in electromagnet design, magnetic materials and some legacy technical documentation.
Using magnetic field units
Ampere per meter is the SI-form unit for magnetic field strength. The oersted remains common in older and specialized magnetic material data.
Check whether a specification refers to field strength, flux density or magnetization before comparing values.
Unit comparison table
| Unit | Symbol | SI equivalent | System | Common use |
|---|---|---|---|---|
| Ampere per Meter | A/m | SI reference unit | SI | Magnetic field strength and electromagnets |
| Oersted | Oe | ≈ 79.5775 A/m | CGS/legacy | Magnetic material and legacy specifications |
Units
| Unit | Symbol | Information |
|---|---|---|
| Ampere per Meter | A/m | View unit guide |
| Oersted | Oe | View unit guide |