The SI unit is Tesla (T). Enter any value to convert all units instantly.
The SI unit is Ampere per metre (A/m). Enter any value to convert all units instantly.
Field Reference & Unit Guide
What is magnetic flux density (B)?
Magnetic flux density (B) measures the strength of a magnetic field passing through a surface. It is the most commonly used quantity when specifying permanent magnets, MRI machines, and laboratory electromagnets.
What is magnetic field strength (H)?
Magnetic field strength (H) describes the magnetising force that drives a magnetic field through a material. It is related to B by the permeability of the medium: B = μH. H is especially useful when working with magnetic circuits and core materials.
Key conversion factors
| From | To Tesla (T) | Reference |
|---|---|---|
| 1 T | = 1 T | Earth MRI field: 1.5–3 T |
| 1 mT | = 10⁻³ T | Fridge magnet: ~5 mT |
| 1 μT | = 10⁻⁶ T | Earth's field: 25–65 μT |
| 1 nT | = 10⁻⁹ T | Brain magnetism: ~100 nT |
| 1 G | = 10⁻⁴ T | 1 T = 10,000 G |
| 1 kG | = 0.1 T | Neodymium: 3–15 kG |
| 1 Wb/m² | = 1 T | Wb/m² ≡ Tesla by definition |
| 1 Oe (H) | = 79.5775 A/m (H-field only) | |
Frequently Asked Questions
What is the difference between Tesla and Gauss?
Both measure magnetic flux density (B). 1 Tesla = 10,000 Gauss. Tesla is the SI unit; Gauss is used in the CGS system and is still common in older literature and some industry applications.
When do I use Oersted instead of A/m?
Oersted measures magnetic field strength (H) in the CGS system, while A/m is the SI equivalent. 1 Oe = 79.5775 A/m. Use Oe when working with older references or CGS-based material datasheets.
What are typical magnetic field values in everyday life?
Earth's magnetic field is about 25–65 μT. A refrigerator magnet is roughly 5 mT. A clinical MRI scanner operates at 1.5–3 T. Neodymium permanent magnets can reach 1–1.4 T at their surface.