Voltage Converter
Free Voltage Converter for electrical & magnetic units. Enter a value to see equivalent measurements across systems. Enter your values for instant results.
Calculator
Adjust values & calculateAll Conversions
| Unit | Value |
|---|---|
| Volt (V) | 1.200000e+2 |
| Kilovolt (kV) | 1.200000e-1 |
| Megavolt (MV) | 1.200000e-4 |
| Millivolt (mV) | 1.200000e+5 |
| Microvolt (uV) | 1.200000e+8 |
| Nanovolt (nV) | 1.200000e+11 |
| Gigavolt (GV) | 1.200000e-7 |
| Abvolt | 1.200000e+10 |
| Statvolt | 4.002769e-1 |
| Watt per ampere (W/A) | 1.200000e+2 |
Formula
Voltage conversion uses the volt (V) as the base SI unit. Metric prefixes scale by powers of 10 (mV = 10^-3 V, kV = 10^3 V, etc.). CGS units convert through fixed physical constants: the abvolt equals 10^-8 V and the statvolt equals approximately 299.79 V. Watt per ampere is dimensionally identical to volts.
Last reviewed: December 2025
Worked Examples
Example 1: Power Supply Voltage Conversion
Example 2: Transmission Line Voltage
Background & Theory
The Voltage Converter applies the following established principles and formulas. Unit conversion is the process of expressing a quantity in a different unit of measurement while preserving its physical meaning. At the foundation of modern measurement lies the International System of Units (SI), which defines seven base units: the meter for length, kilogram for mass, second for time, ampere for electric current, kelvin for thermodynamic temperature, mole for amount of substance, and candela for luminous intensity. All other units, called derived units, are defined as algebraic combinations of these seven. Dimensional analysis is the principal method for performing unit conversions. By treating units as algebraic quantities that can be multiplied, divided, and cancelled, a conversion factor chain allows a value expressed in one unit to be rewritten in another without altering its physical magnitude. For example, to convert 60 miles per hour to meters per second, one multiplies by a chain of conversion factors each equal to one: (1609.34 m / 1 mile) × (1 hour / 3600 s). Metric prefixes enable compact expression of quantities across extreme ranges of magnitude. Standard prefixes span from nano (10^-9) through micro (10^-6) and milli (10^-3) up through kilo (10^3), mega (10^6), and giga (10^9), and beyond in both directions. These prefixes are strictly multiplicative and apply consistently to any SI base or derived unit. Temperature conversions require affine transformations rather than simple scaling. To convert Celsius to Fahrenheit the formula is °F = (°C × 9/5) + 32, while the conversion to the absolute Kelvin scale is K = °C + 273.15. These formulas reflect the different zero points and degree-size conventions of each scale. Significant figures govern how precision is preserved through calculations. A result should not express more precision than the least precise input value permits. In digital storage, IEEE and IEC standards distinguish between decimal prefixes (kilobyte = 1000 bytes) and binary prefixes (kibibyte = 1024 bytes), a distinction that has practical consequences for how storage capacity is reported by manufacturers versus operating systems. Unit coherence — ensuring that all quantities in an equation share a consistent unit system — is essential for obtaining correct results.
History
The history behind the Voltage Converter traces back through the following developments. Human beings have been measuring and comparing quantities since before recorded history. The earliest known measurement units were body-based: the cubit (the distance from elbow to fingertip), the foot, the hand, and the digit. The furlong originated as the length of a furrow a team of oxen could plow without resting. These anthropomorphic standards were practical for local use but differed between regions and kingdoms, creating persistent difficulties in trade and construction. The ancient Egyptians standardized the royal cubit at approximately 52.4 centimeters and distributed calibrated granite rods to ensure consistency across building projects, including the pyramids. Roman engineers used the mile (mille passuum, one thousand double paces) and spread these standards throughout their empire via road networks. Despite these efforts, measurement diversity persisted across medieval Europe, hampering commerce. The French Revolution created political will for radical standardization. In 1795 France officially adopted the metric system, defining the meter as one ten-millionth of the distance from the equator to the North Pole along the Paris meridian. This gave the world its first fully decimal, rationally constructed measurement system. The Metre Convention of 1875 established the International Bureau of Weights and Measures (BIPM) in Sevres, France, creating a permanent international body to maintain physical artifact standards and coordinate global metrology. For over a century, the kilogram was defined by a platinum-iridium cylinder locked in a vault near Paris. In 1999, a stark demonstration of what unit inconsistency costs occurred when NASA's Mars Climate Orbiter was lost because one engineering team used pound-force seconds while another used newton seconds. The spacecraft entered the Martian atmosphere at the wrong angle and was destroyed, at a cost of 327 million dollars. In 2019 the SI underwent its most significant revision, redefining all seven base units in terms of fixed numerical values of fundamental physical constants such as the speed of light, Planck's constant, and the elementary charge. This eliminated any reliance on physical artifacts and made the measurement system permanently stable and universally reproducible.
Frequently Asked Questions
Sources & References
Formula
Converted Value = Input x (From Unit Factor / To Unit Factor)
Voltage conversion uses the volt (V) as the base SI unit. Metric prefixes scale by powers of 10 (mV = 10^-3 V, kV = 10^3 V, etc.). CGS units convert through fixed physical constants: the abvolt equals 10^-8 V and the statvolt equals approximately 299.79 V. Watt per ampere is dimensionally identical to volts.
Worked Examples
Example 1: Power Supply Voltage Conversion
Problem: A sensor outputs 3300 millivolts. Express this in volts, microvolts, and kilovolts.
Solution: 3300 mV to V: 3300 x 0.001 = 3.3 V\n3300 mV to uV: 3300 x 1000 = 3,300,000 uV\n3300 mV to kV: 3300 x 0.000001 = 0.0033 kV\nThis is a common logic-level voltage for microcontrollers.
Result: 3300 mV = 3.3 V = 3,300,000 uV = 0.0033 kV
Example 2: Transmission Line Voltage
Problem: A high-voltage transmission line operates at 345 kV. Convert to volts and megavolts.
Solution: 345 kV to V: 345 x 1000 = 345,000 V\n345 kV to MV: 345 / 1000 = 0.345 MV\nThis is a standard extra-high-voltage (EHV) transmission level in North America.
Result: 345 kV = 345,000 V = 0.345 MV
Frequently Asked Questions
What are typical voltage levels in electrical systems?
Common voltage levels vary widely by application. AA batteries produce 1.5 V, USB ports supply 5 V, car batteries provide 12 V, and US household outlets deliver 120 V RMS (170 V peak). European households use 230 V. Industrial equipment often runs on 480 V three-phase power. Power distribution lines carry 4-35 kV, and high-voltage transmission lines operate at 115-765 kV. Lightning strikes can reach hundreds of millions of volts momentarily.
How does voltage relate to current and power?
Voltage, current, and power are related by fundamental electrical laws. Ohm Law states V = I x R (voltage equals current times resistance). The power equation states P = V x I (power equals voltage times current). Combining these gives P = V^2/R and P = I^2 x R. These relationships are essential for electrical engineering, circuit design, and power system calculations. Higher voltage allows the same power to be transmitted with less current, reducing losses in transmission lines.
How accurate are the results from Voltage Converter?
All calculations use established mathematical formulas and are performed with high-precision arithmetic. Results are accurate to the precision shown. For critical decisions in finance, medicine, or engineering, always verify results with a qualified professional.
Why might my result differ from another tool or reference?
Differences typically arise from rounding conventions, the specific version of a formula (for example, simple vs compound interest), or unit inconsistencies between inputs. Check that both tools are using the same formula variant and the same units. The References section links to the authoritative source behind the formula used here.
How do I interpret the result?
Results are displayed with a label and unit to help you understand the output. Many calculators include a short explanation or classification below the result (for example, a BMI category or risk level). Refer to the worked examples section on this page for real-world context.
Does Voltage Converter work offline?
Once the page is loaded, the calculation logic runs entirely in your browser. If you have already opened the page, most calculators will continue to work even if your internet connection is lost, since no server requests are needed for computation.
References
Reviewed by Manoj Kumar, Mathematics Educator · Editorial policy