Calculator
Select a model, enter inputs, then calculate zeta potential.
Formula used
This calculator uses Henry’s relation for electrophoresis:
μ = (2 ε ζ f(κa)) / (3 η) ⇒ ζ = (3 η μ) / (2 ε f(κa))
- μ = electrophoretic mobility (m²/(V·s))
- η = dynamic viscosity (Pa·s)
- ε = ε0 εr (F/m)
- f(κa) = Henry function (dimensionless)
Notes: Smoluchowski uses f=1.5, Hückel uses f=1.0. Henry auto uses a smooth approximation from 1 to 1.5 as κa increases.
How to use this calculator
- Select a model that matches your electrolyte and particle size regime.
- Enter mobility, viscosity, and relative permittivity with correct units.
- If using Henry, choose auto κa or provide manual f(κa).
- Press Calculate to display zeta potential above the form.
- Use the CSV or PDF buttons to export your results.
Example data
Sample inputs and typical outputs for quick testing.
| Mobility (10^-8 m²/V·s) | η (Pa·s) | εr | Model | κa / f | Expected ζ (mV) |
|---|---|---|---|---|---|
| 3.50 | 0.00089 | 78.5 | Smoluchowski | f=1.5 | ~45 |
| -2.20 | 0.00100 | 80.0 | Hückel | f=1.0 | negative |
| 1.80 | 0.00120 | 60.0 | Henry | κa=2 | depends |