Magnetic Flux Converter
Convert magnetic flux between weber, maxwell, line, kiloline, megaline, volt second, tesla square meter, unit pole, the magnetic flux quantum and more. Pick a source and a target unit, enter a value and read the result instantly.
Select two units to see the conversion factor.
Magnetic flux (weber, maxwell) is not magnetic flux density (tesla, gauss). Flux is the total through an area; flux density is flux per unit area, so converting between them needs an area.
Magnetic Flux Formula
Every flux unit is a fixed multiple of one reference unit, the weber (Wb). To convert, multiply the value by the size of the source unit in webers, then divide by the size of the target unit in webers. Key exact relationships: 1 Wb = 1 V·s = 1 T·m², 1 maxwell = 1 line = 1 G·cm² = 10⁻⁸ Wb, 1 unit pole = 4π maxwell, and the flux quantum is Φ₀ = h ÷ (2e), about 2.0678 × 10⁻¹⁵ Wb.
What Is Magnetic Flux?
Magnetic flux, written Φ, is the total amount of magnetic field passing through a surface. For a uniform field at right angles to a surface it equals the flux density times the area: Φ = B × A. The SI unit is the weber (Wb), which equals one tesla square meter (T·m²) and, through Faraday’s law, one volt second: a flux that changes at 1 Wb per second induces 1 V in a single turn.
The CGS unit is the maxwell (Mx), equal to one gauss square centimeter (G·cm²) and to exactly 10⁻⁸ Wb. Older engineering practice counts flux in lines (a line is one maxwell), kilolines and megalines. A unit pole is the flux emitted by a unit magnetic pole and equals 4π maxwell, about 1.2566 × 10⁻⁷ Wb.
The magnetic flux quantum, Φ₀ = h ÷ (2e), is a fundamental constant: the smallest unit of flux that can thread a superconducting loop. With the exact SI values of the Planck constant and the elementary charge it is about 2.067834 × 10⁻¹⁵ Wb.
Magnetic flux must be distinguished from flux density B (tesla, gauss), which is flux per unit area, from magnetic field strength H (A/m) and from magnetomotive force (ampere-turn). This converter only changes between flux units.
Supported Units
This converter supports the following 13 magnetic flux units. The last column shows how many webers one unit equals. The maxwell, the line and the gauss square centimeter are three names for the same quantity of flux, 10⁻⁸ Wb.
| Unit | Symbol | Value in Wb |
|---|---|---|
| Weber | Wb | 1 |
| Milliweber | mWb | 0.001 |
| Microweber | µWb | 1e-6 |
| Volt second | V·s | 1 |
| Unit pole | unit pole | 1.256637061e-7 |
| Megaline | Mline | 0.01 |
| Kiloline | kline | 1e-5 |
| Line | line | 1e-8 |
| Maxwell | Mx | 1e-8 |
| Tesla square meter | T·m² | 1 |
| Tesla square centimeter | T·cm² | 0.0001 |
| Gauss square centimeter | G·cm² | 1e-8 |
| Magnetic flux quantum | Φ₀ | 2.067833848e-15 |
How to Use the Magnetic Flux Converter
- Type the magnetic flux in the value box. Decimals and scientific notation such as 0.0025 or 2.5e-3 are accepted.
- Choose the From unit and the To unit.
- The result appears instantly, or press Convert Now. Very large or very small results are shown in scientific notation.
- Use Swap Units to reverse the conversion, Copy Result to copy the answer, open Show this value in all units for a full list, and Clear to start again.
Step-by-step by hand
- Find the size of each unit in the common base unit (Wb): 1 Mx = 1e-8 Wb and 1 Wb = 1 Wb.
- Divide the source size by the target size to get the conversion factor: 1e-8 ÷ 1 = 1e-8, so 1 Mx = 1e-8 Wb.
- Multiply by your value: 100,000 Mx × 1e-8 = 0.001 Wb.
Flux cannot be negative in this tool, so only zero and positive numbers are accepted; the sign of a flux only gives its direction.
Common Magnetic Flux Conversions
- CGS to SI: 100,000 Mx equals 0.001 Wb, which is 1,000 µWb.
- SI to CGS: 2 mWb equals 200,000 Mx, or 200 kilolines.
- Old engineering data: 5 megalines equals 50 mWb.
- Field times area: a uniform 0.5 T field through 0.02 m² gives Φ = 0.01 Wb, which is 1,000,000 Mx.
- Volt second: 3 V·s equals 3 Wb.
- Unit pole: 2 unit poles equal 2.513274123e-7 Wb.
- Flux quantum: 1 Φ₀ equals 2.067833848e-15 Wb.
Maxwell to Weber – Common Values
Quick reference for frequently used values
| Maxwell | Weber | Microweber | Kiloline |
|---|---|---|---|
| 1 | 1e-8 | 0.01 | 0.001 |
| 100 | 1e-6 | 1 | 0.1 |
| 1,000 | 1e-5 | 10 | 1 |
| 10,000 | 0.0001 | 100 | 10 |
| 100,000 | 0.001 | 1,000 | 100 |
| 1,000,000 | 0.01 | 10,000 | 1,000 |
| 100,000,000 | 1 | 1,000,000 | 100,000 |
Where and Why This Conversion Is Used
- Transformers, motors and inductors: core flux is calculated in webers or milliwebers and compared with CGS data.
- Magnet and loudspeaker data sheets: older documents give total flux in maxwell or kilolines.
- Induction and Faraday’s law: flux linkage in V·s relates to induced voltage.
- Superconducting devices and SQUIDs: flux is counted in units of the flux quantum Φ₀.
- Teaching: comparing SI and CGS magnetic units.
Important Differences Between Related Magnetic Quantities
- Magnetomotive force, F (ampere-turn, gilbert): the “driving force” of a magnetic circuit, F = N × I.
- Magnetic field strength, H (A/m, oersted): magnetomotive force per unit length of the magnetic path.
- Magnetic flux density, B (tesla, gauss): how strong the resulting magnetic field is, and the flux per unit area. In a material B = μ × H.
- Magnetic flux, Φ (weber, maxwell): the total magnetic field passing through an area, Φ = B × A.
These four quantities have different dimensions, so none of them can be converted into another by a unit factor. Moving between them needs extra information such as a length, an area or the permeability of the material. Each converter here only changes units within one quantity. See the Magnetomotive Force Converter, Magnetic Field Strength Converter, Magnetic Flux Converter and Magnetic Flux Density Converter.