This electric field strength converter changes a field between volts per meter, kilovolts and millivolts per meter, volts and kilovolts per centimeter, volts per inch and statvolts per centimeter. Formula: 1 V/cm = 100 V/m; 1 N/C = 1 V/m. The SI unit is V/m, which equals newtons per coulomb, so N/C to V/m is a factor of 1. 1 kV/cm is exactly 100,000 V/m.
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How to use the electric field strength converter
- Enter the field, for example 30 kV/cm.
- In the electric field strength converter, choose its unit and the target unit, such as kV/cm to V/m.
- Read the electric field strength converter result: 30 kV/cm = 3,000,000 V/m.
For V/m to kV/cm, divide by 100,000. For kV/mm to V/m, multiply by 1,000,000. For N/C to V/m, the number does not change.
What is electric field strength?
Electric field strength is the force per unit charge at a point in space, expressed in volts per meter (V/m), which equals newtons per coulomb. It is used in insulation design, EMC testing and atmospheric physics.
Conversion formula
The electric field strength converter stores every unit as a multiple of the base unit, the volt per meter (V/m). To convert:
value in target unit = value × (factor of source unit ÷ factor of target unit)
where each factor is the size of the unit in volts per meter.
Common electric field strength conversions
| From | To | 1 unit equals |
|---|---|---|
| volt per meter (V/m) | volt per centimeter (V/cm) | 0.01 V/cm |
| kilovolt per meter (kV/m) | volt per meter (V/m) | 1,000 V/m |
| volt per centimeter (V/cm) | volt per meter (V/m) | 100 V/m |
Electric field strength converter worked example
Convert 25 volts per meter to volts per centimeter:
- Factor of V/m = 1 V/m
- Factor of V/cm = 100 V/m
- 25 × 1 ÷ 100 = 0.25 V/cm
Electric field strength unit reference
| Unit | Symbol | Group | Equals (V/m) |
|---|---|---|---|
| Volt per Meter | V/m | SI | 1 |
| Kilovolt per Meter | kV/m | SI | 1,000 |
| Millivolt per Meter | mV/m | SI | 0.001 |
| Volt per Centimeter | V/cm | SI | 100 |
| Kilovolt per Centimeter | kV/cm | SI | 100,000 |
| Volt per Inch | V/in | US/Imperial | 39.37007874 |
| Statvolt per Centimeter | statV/cm | CGS-ESU | 29,979.2458 |
Reverse factors for each electric field strength unit
The reference table gives each unit in volt per meters. To go the other way, divide by that factor; the list below does the division for you.
- Kilovolt per Meter (kV/m), SI: 1 kV/m = 1,000 V/m, so 1 V/m = 0.001 kV/m.
- Millivolt per Meter (mV/m), SI: 1 mV/m = 0.001 V/m, so 1 V/m = 1,000 mV/m.
- Volt per Centimeter (V/cm), SI: 1 V/cm = 100 V/m, so 1 V/m = 0.01 V/cm.
- Kilovolt per Centimeter (kV/cm), SI: 1 kV/cm = 100,000 V/m, so 1 V/m = 1 × 10−5 kV/cm.
- Volt per Inch (V/in), US/Imperial: 1 V/in = 39.37008 V/m, so 1 V/m = 0.0254 V/in.
- Statvolt per Centimeter (statV/cm), CGS-ESU: 1 statV/cm = 29,979.25 V/m, so 1 V/m = 3.33564 × 10−5 statV/cm.
Dielectric strength: kV/mm and V/mil
Insulation datasheets give dielectric strength in kV/mm in metric markets and in volts per mil (thousandth of an inch) in the US. Since 1 mil = 25.4 µm, 1 kV/mm = 25.4 V/mil and 1 V/mil ≈ 39,370 V/m:
| kV/mm | V/mil | V/m | kV/cm |
|---|---|---|---|
| 1 | 25.4 | 1,000,000 | 10 |
| 3 | 76.2 | 3,000,000 | 30 |
| 10 | 254 | 10,000,000 | 100 |
| 20 | 508 | 20,000,000 | 200 |
| 50 | 1,270 | 50,000,000 | 500 |
Measured strength depends on thickness and test method, so compare values from the same standard. Dry air at sea level breaks down at roughly 3 kV/mm.
Field from voltage and distance
Between parallel plates, E = V ÷ d. 1,000 V across a 1 mm gap is 1 kV/mm, or 1,000,000 V/m. Near the ground in fair weather, the atmosphere has a vertical field of roughly 100 V/m, which rises sharply under thunderclouds. The force on a charge is F = qE, which is why V/m and N/C are the same unit. Use the voltage converter for V and kV and the length converter for gaps in inches or mils.
Air breakdown in other units
Dry air at sea level breaks down at roughly 3 MV/m. The electric field strength converter shows this as 30 kV/cm or about 76 kV/in. Humidity, pressure and electrode shape all shift the real value.
Insulation data sheets use kV/mm. One kV/mm equals 1 MV/m, so air’s figure is about 3 kV/mm.
Related converters and calculators
Related electrical tools:
- Voltage converter: V and mV
- Electric charge converter: C and mAh
- Surface charge density converter: C/m²
- Linear charge density converter: C/m
- Capacitance converter: F, µF, pF
Sources
NIST Special Publication 811, Appendix B; BIPM: SI Brochure.
Questions about this calculator
Is V/m the same as N/C?
Yes. 1 V/m = 1 N/C.
How do I convert V/m to kV/cm?
Divide by 100,000. For example, 3,000,000 V/m = 30 kV/cm.
How do I convert kV/mm to V/m?
Multiply by 1,000,000. For example, 2 kV/mm = 2,000,000 V/m.
How do I convert kV/mm to V/mil?
Multiply by 25.4. For example, 20 kV/mm = 508 V/mil.
What is a statvolt per centimeter?
The CGS unit, equal to 29,979.2458 V/m.
Check the assumptions and units before relying on a result. Financial, tax and health estimates do not replace advice for your individual circumstances.
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