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Magnetic Permeability Calculator.

Calculate absolute and relative permeability from flux density and field strength.

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Set your values

Results update as you type.

Permeability: 0.00001 H/m

Permeability

0.000010H/m
Relative permeability: 7.957747

Relative permeability

7.957747

Results update automatically as you type.

Use Cases

Material characterization

Engineers and physicists use permeability values to compare magnetic materials for cores, transformers, and inductors.

Example: Enter B = 1.2 T and H = 800 A/m to find μ and μr for a steel sample.

Educational demonstrations

Students can verify the relationship between flux density, field strength, and permeability in electromagnetism labs.

Example: Check how μr changes for air (≈1) vs. iron (hundreds or thousands).

Frequently Asked Questions

What does this calculator compute?
It computes absolute permeability (in henries per meter) and relative permeability (dimensionless) from the magnetic flux density (in teslas) and magnetic field strength (in amperes per meter) you input.
How is relative permeability derived?
Relative permeability is the ratio of absolute permeability to the permeability of free space (μ₀ ≈ 4π × 10⁻⁷ H/m). It indicates how much a material concentrates magnetic flux compared to a vacuum.
What units are used for the inputs?
Magnetic flux density must be entered in teslas (T), and magnetic field strength in amperes per meter (A/m). The calculator uses these SI units to compute permeability.

Tips & Common Mistakes

Tips

  • Ensure both inputs are in SI units: teslas for flux density and amperes per meter for field strength.
  • For linear materials, permeability is constant, but for ferromagnetic materials it varies with field strength.
  • Relative permeability is unitless; absolute permeability is in henries per meter (H/m).
  • Use typical values: air μr ≈ 1, iron μr can be 200–5000, depending on composition.

Common Mistakes to Avoid

  • Using gauss instead of tesla for flux density (1 T = 10,000 G).
  • Confusing absolute and relative permeability—relative is a ratio, not in H/m.
  • Entering field strength in oersteds instead of A/m (1 Oe ≈ 79.577 A/m).

Last updated: August 13, 2026