Hall Coefficient Calculator - R_H, Carrier Density & Type

Hall coefficient calculator from Hall voltage, current, magnetic field, and thickness. Read R_H in m^3/C, carrier density, and n-type or p-type sign.

Updated: July 8, 2026 • Free Tool

Hall Coefficient Calculator

Voltage measured across the sample width when the field is applied. Use a negative value for p-type behavior.

Lengthwise current through the sample.

Perpendicular magnetic flux density in Tesla. Divide Gauss by 10,000 to convert.

Sample thickness in the direction of the field, in metres.

Results

Hall coefficient R_H
0m^3/C
Carrier density n 01/m^3
Carrier type 0

What Is the Hall Coefficient Calculator?

The hall coefficient calculator finds the Hall coefficient R_H of a conductor or semiconductor from four measured quantities: Hall voltage V_H, current I, magnetic field B, and sample thickness t. R_H describes how strongly a material develops a transverse voltage when a magnetic field is applied across a current-carrying strip, and its sign immediately tells you whether electrons or holes carry the current.

  • Semiconductor doping check: Lab students measure V_H and infer whether a sample is n-type or p-type and how heavily it is doped.
  • Carrier density from a Hall bar: Turn a Hall measurement into a number density n without needing a separate mass or molar route.
  • Solid-state physics coursework: Verify the relation R_H = -1/(n e) against measured voltages for copper, silicon, or germanium.
  • Sensor design sanity check: Estimate the expected Hall voltage for a given bias current and field before building a Hall sensor.

A Hall measurement is one of the few experiments that reveals the sign of the dominant charge carrier, which is why it sits at the center of introductory solid-state physics.

This calculator also reports carrier density n from R_H using the single-carrier formula and labels the sample n-type or p-type from the sign of R_H.

If you already know the current and carrier density, the drift velocity calculator converts those into the mean carrier speed.

How the Hall Coefficient Calculator Works

The hall coefficient calculator applies the standard Hall relation directly. You enter the measured Hall voltage, the current, the perpendicular magnetic field, and the thickness, and it returns R_H, the carrier density, and the carrier type.

R_H = (V_H x t) / (I x B), n = -1 / (e x R_H)
  • V_H: Hall voltage in volts, measured across the sample width.
  • I: Current in amperes flowing lengthwise through the sample.
  • B: Magnetic flux density in tesla, applied perpendicular to the current.
  • t: Sample thickness in metres, the dimension along which V_H develops.
  • e: Elementary charge, 1.602176634 x 10^-19 C, used to recover carrier density.

The Hall voltage comes from the Lorentz force bending moving carriers sideways until a transverse electric field balances it; R_H is simply that field divided by the product of current density and magnetic field.

Because V_H is typically microvolts to millivolts, keep your inputs in consistent SI units: volts, amperes, tesla, and metres. If you measure B in Gauss, divide by 10,000 before entering it, so the result lands in the correct m^3/C range.

Copper strip

V_H = 3.65 x 10^-13 V, I = 0.01 A, B = 0.5 T, t = 1 x 10^-3 m.

R_H = (3.65e-13 x 1e-3) / (0.01 x 0.5) = 3.65e-16 / 5e-3 = -7.3 x 10^-11 m^3/C. Then n = -1 / (1.602e-19 x -7.3e-11) = 8.5 x 10^28 1/m^3.

R_H = -7.3 x 10^-11 m^3/C, n = 8.5 x 10^28 1/m^3, carrier type n-type.

The negative R_H and huge density match metallic copper, where nearly one conduction electron per atom is free.

According to HyperPhysics (Hall Effect), the Hall voltage V_H arises because the Lorentz force on moving carriers is balanced by a transverse electric field, and is proportional to I B / t.

Per Wikipedia (Hall effect), the Hall coefficient reduces to -1/(n e) for a single carrier type, with the sign set by the carrier charge.

Mobility connects carrier speed to the applied field; the electrical mobility calculator works from the Einstein relation.

Key Concepts Explained

Four ideas explain why the Hall coefficient is so informative. Together they link a transverse voltage to the number and sign of the charge carriers moving through a material.

Hall voltage

The small transverse voltage V_H that appears across a current-carrying strip when a perpendicular magnetic field is switched on.

Carrier density n

The number of free charge carriers per cubic metre. From R_H, n = -1/(e R_H) for a single carrier type; a larger magnitude R_H means a lower density.

Carrier type and sign

Negative R_H means electrons dominate (n-type); positive R_H means holes dominate (p-type). The sign is the fastest way to identify the majority carrier.

Hall coefficient units

In SI, R_H is expressed in cubic metres per coulomb (m^3/C), because it is a transverse voltage times a length divided by current times magnetic field.

The units follow directly from the formula: volts times metres over amperes times tesla reduces to m^3/C.

Keeping magnitudes straight matters: metals have R_H near 10^-11 m^3/C while semiconductors sit near 10^-3 m^3/C, a millionfold difference driven by carrier density.

Sign convention matters when you compare values against a reference. This calculator treats negative R_H as n-type because electrons carry negative charge, matching the standard physics convention. Some engineering texts quote the Hall coefficient as a positive magnitude instead, so confirm the sign rule of your source before matching a published number.

Resistivity pairs with the Hall coefficient to define the Hall factor; use the conductivity to resistivity calculator to switch between them.

How to Use This Calculator

Follow these steps to turn a Hall measurement into a carrier profile. The hall coefficient calculator only needs four measured quantities, so the routine fits a lab notebook or a quick design check.

  1. 1 Measure the Hall voltage: Record V_H across the sample width with the field applied; note its sign.
  2. 2 Enter the current: Type the lengthwise current I in amperes.
  3. 3 Enter the magnetic field: Enter B in tesla. Convert Gauss by dividing by 10,000.
  4. 4 Enter the thickness: Enter the sample thickness t in metres.
  5. 5 Read the results: Read R_H, the carrier density n, and the n-type or p-type label.
  6. 6 Cross-check the sign: Confirm the sign of R_H matches the expected carrier type for your material.

Practical example: a silicon Hall bar carrying 10 mA in a 0.5 T field shows V_H = 31.2 mV across a 1 mm thickness. Entering those values returns R_H = -6.24 x 10^-3 m^3/C and n = 1.0 x 10^21 1/m^3, confirming an n-type sample.

When you need carrier density from a different route, the number density calculator derives it from mass and molar data.

Benefits of Using This Calculator

The hall coefficient calculator turns a four-number measurement into a clear material verdict, which is why it appears in solid-state physics labs and semiconductor process control alike.

  • Direct carrier identification: The sign of R_H labels n-type versus p-type without manual algebra.
  • Doping density at a glance: Recovering n from R_H estimates how heavily a semiconductor is doped.
  • Unit consistency guard: SI-only inputs remove the common mixed-unit (Gauss versus Tesla) mistake.
  • Teaching clarity: Worked output reinforces the R_H = -1/(n e) relation for students.
  • Design pre-check: Predict Hall voltage before committing to a sensor bias current and field.

Rather than juggling powers of ten by hand, you see the density in standard 1/m^3 units immediately.

The calculator also surfaces when an input would divide by zero, keeping edge cases honest.

The Hall measurement supplements the resistance you read with an Ohm's law calculator to infer doping.

Factors That Affect Your Results

Several real-world effects shift the Hall coefficient away from the simple single-carrier value. The hall coefficient calculator reports the single-band R_H, so knowing where that assumption breaks down keeps your interpretation honest.

Multiple carrier types

Metals and doped semiconductors can carry both electrons and holes; the simple formula assumes one band and will be approximate when the two contributions are comparable.

Magnetic-field strength

R_H itself is field-independent in the simple model, but at high B, magnetoresistance and band effects change the measured V_H you feed in.

Sample geometry

Thickness t and the current path must match the assumed geometry; a mis-measured t scales R_H linearly because it sits in the numerator.

Temperature

Carrier density and mobility change with temperature, so R_H and n are temperature-dependent quantities rather than fixed constants.

  • The single-carrier formula R_H = -1/(n e) is an approximation; materials with two comparable carrier types need a two-band model.
  • Very small V_H near noise floor gives uncertain R_H; use clean, amplified measurements for reliable density.

Treat the output as the single-band Hall coefficient; for accurate doping in a two-carrier material, fit field-dependent data instead.

Always report the temperature at which R_H and n were measured, since both vary with it. A symmetric offset voltage when the field is reversed also shifts V_H; measure at +B and -B and take half the difference to cancel it.

Per Wikipedia (Electron mobility), many real conductors carry more than one carrier type, and mobility links to conductivity through μ = σ/(n e), so the single-band formula R_H = -1/(n e) is an approximation valid near the single-carrier limit.

Because the Hall field is an electric field in equilibrium, the Gauss's law calculator helps reason about the transverse field geometry.

Hall coefficient calculator showing Hall voltage, current, magnetic field, and thickness inputs with Hall coefficient, carrier density, and carrier type outputs
Hall coefficient calculator showing Hall voltage, current, magnetic field, and thickness inputs with Hall coefficient, carrier density, and carrier type outputs

Frequently Asked Questions

Q: What is the Hall coefficient?

A: It is a material property, R_H, that equals the transverse electric field divided by the product of current density and perpendicular magnetic field. For a single carrier type R_H = -1/(n e), so its magnitude grows as carrier density falls and its sign reveals the carrier charge.

Q: How do you calculate the Hall coefficient from Hall voltage?

A: Use R_H = (V_H x t) / (I x B), with V_H the transverse voltage, t the sample thickness, I the current, and B the magnetic field in tesla. Enter those four values and the calculator returns R_H directly.

Q: What units does the Hall coefficient use?

A: In SI units the Hall coefficient is measured in cubic metres per coulomb (m^3/C). This follows because volts times metres divided by amperes times tesla reduces to m^3/C.

Q: Why is the Hall coefficient positive for some materials and negative for others?

A: The sign follows the dominant carrier. Electrons give a negative R_H (n-type), while holes give a positive R_H (p-type). This is why a Hall measurement identifies whether a semiconductor is n-type or p-type.

Q: How is carrier density found from the Hall coefficient?

A: For one carrier type, rearrange R_H = -1/(n e) to n = -1/(e x R_H), using e = 1.602176634 x 10^-19 C. The calculator does this step and reports n in carriers per cubic metre.

Q: What does a large or small Hall coefficient tell you about a material?

A: A small magnitude (metals, near 10^-11 m^3/C) means a very high carrier density; a large magnitude (semiconductors, near 10^-3 m^3/C) means a low carrier density. The six-order difference is driven almost entirely by how many free carriers are present.