Electrical Conductance Conversion Calculator
Written by Thierno Sadou Diallo, formula verified per our methodology • Last checked on 9/10/2026
To convert an electrical conductance, it is reduced to siemens (S), then converted into the desired unit. Example: a conductance of 500 mS equals 0.5 S.
Explanation
The siemens (S), the SI unit of electrical conductance, measures how easily a component lets electric current pass — the exact mathematical inverse of resistance (1 siemens = 1 ÷ 1 ohm). A high conductance therefore corresponds to a low resistance, and vice versa: a good electrical conductor has a high conductance, while an insulator has a conductance close to zero. This unit, also historically called the "mho" (the word "ohm" read backwards, a nod still found in some older texts), is used notably in chemistry and biology to measure the conductivity of a solution or a cell membrane, as well as in electronics to characterize components such as field-effect transistors. This calculator converts a conductance value already expressed in this unit; to convert resistance itself (the inverse of conductance), see our electrical resistance conversion calculator.
Example: a conductance of 500 mS
Inputs
Value: 500. Starting unit: mS. Target unit: S.
Calculation
The "milli" prefix means 10⁻³: 500 mS = 500 × 10⁻³ S = 0.5 S.
Result
A conductance of 500 mS equals 0.5 S.
Frequently asked questions
How do you go directly from resistance to conductance?
By taking the mathematical inverse of the value: conductance (S) = 1 ÷ resistance (Ω). A resistance of 200 Ω therefore corresponds to a conductance of 1 ÷ 200 = 0.005 S, that is 5 mS. This calculator converts a conductance already expressed in siemens to another scale, without performing that inversion from a resistance.
Why is this unit sometimes called the "mho"?
The name "mho" ("ohm" written backwards) was used historically to highlight the inverse relationship between conductance and resistance, before the official adoption of the name "siemens" by the International System in honor of the German engineer Werner von Siemens. The term "mho" is still occasionally used in older texts or some North American contexts.
In which fields is conductance most used?
Beyond electronics, conductance (often expressed in microsiemens) is commonly used to measure water quality: very pure water has a very low conductance, while water rich in dissolved salts (minerals, sea salt) conducts current much better and shows a markedly higher conductance.
Does this concept appear in Ohm's law?
Yes, in its inverse form: Ohm's law is usually written I = V ÷ R, but can also be expressed with conductance G (I = V × G), the two formulations being strictly equivalent. See our Ohm's law calculator for the most common version of this relationship.