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Electrical Unit Converter

Convert voltage, current, resistance, and power across every metric prefix — millivolts, volts, kilovolts; microamps, milliamps, amps; ohms, kilo-ohms, mega-ohms; milliwatts, watts, kilowatts.

Electrical Unit Converter

Convert between volts, amps, ohms, and watts at any prefix — millivolts to kilovolts, microamps to amps, ohms to megaohms, milliwatts to kilowatts.

Equivalent values

mV12 k
V12
kV0.012

What Is an Electrical Unit Converter?

An electrical unit converter translates a measurement between the metric prefixes used for voltage, current, resistance, and power. The same physical quantity can be written many ways — 0.0047 amps is 4.7 milliamps is 4,700 microamps — and converting between them quickly and without arithmetic slips is a daily task in electronics, lab work, and field service.

This converter handles the four core electrical quantities: voltage (millivolts, volts, kilovolts), current (microamps, milliamps, amps), resistance (ohms, kilo-ohms, mega-ohms), and power (milliwatts, watts, kilowatts). Pick a quantity and a source unit, type a value, and every equivalent prefix updates live. It is built into the Ohm's Law Calculator so you can convert and compute in the same workspace.

This is one mode of the full Ohm's Law Calculator — you can also jump to the voltage drop calculator or the all-in-one unit converter for related electrical work.

How Electrical Unit Conversion Works

Everything scales by powers of ten

Metric prefixes are pure powers of ten: milli is ÷1,000, kilo is ×1,000, micro is ÷1,000,000, mega is ×1,000,000. Conversion is just shifting the decimal point — no rounding error is introduced.

Convert through the base unit

The converter normalises your input to the base SI unit (volt, amp, ohm, watt), then scales out to every prefix. This guarantees consistency: 1 kΩ and 1,000 Ω always agree to the last digit.

Prefixes are shared across quantities

Milli, kilo, micro, and mega mean the same multiplier whether you apply them to volts, amps, or watts. Learn the prefixes once and they work everywhere in electronics.

Live, synchronized output

Change the value or the source unit and every equivalent updates instantly — no Calculate button. That makes it fast to sanity-check datasheet figures or meter readings on the fly.

Electrical Prefix Multipliers

Every conversion in this tool is a multiply or divide by a power of ten. These are the prefixes used for voltage, current, resistance, and power.

Micro / Milli

µ = ÷10⁶ · m = ÷10³

Microamps and milliamps for small currents; millivolts and milliwatts for signals.

Base unit

V · A · Ω · W

Volt, ampere, ohm, and watt — the SI base units everything scales from.

Kilo / Mega

k = ×10³ · M = ×10⁶

Kilovolts and kilowatts for power systems; kilo-ohms and mega-ohms for high resistance.

How to Use the Electrical Unit Converter

  1. 1

    Choose the quantity

    Select voltage, current, resistance, or power. The unit options update to the prefixes that apply to that quantity.

  2. 2

    Enter the source value and unit

    Type the number you have and pick its unit — for example 4.7 in milliamps, or 2.2 in kilo-ohms.

  3. 3

    Read every equivalent instantly

    The result panel shows the value in every other prefix simultaneously, so you can copy whichever the datasheet, meter, or schematic expects.

  4. 4

    Switch quantities anytime

    Convert a voltage, then jump straight to converting a resistance or a power figure without leaving the page.

Key Conversion Concepts

Volt (V)

The unit of electrical potential. Millivolts (mV) measure sensor signals and thermocouples; kilovolts (kV) measure transmission lines and CRTs.

Ampere (A)

The unit of current. Microamps (µA) flow in op-amp inputs and leakage paths; milliamps (mA) run LEDs and logic; amps drive motors and power supplies.

Ohm (Ω)

The unit of resistance. Ohms measure shunts and heating elements; kilo-ohms bias transistors; mega-ohms appear in insulation and high-impedance inputs.

Watt (W)

The unit of power. Milliwatts rate small resistors and signals; watts rate appliances; kilowatts rate motors, heaters, and service panels.

When You Need Electrical Conversions

📟

Reading a datasheet

A part lists 470 µA quiescent current; your meter reads in mA. Convert to 0.47 mA to compare directly.

🔌

Sizing a resistor

A schematic calls for 4.7 kΩ; your parts bin is labelled in ohms. That's 4,700 Ω — same value, different prefix.

🔋

Battery and solar specs

A panel rated 0.1 kW is 100 W; a cell rated 2,500 mAh is 2.5 Ah. Converting prefixes makes spec sheets comparable.

🧪

Lab measurements

An electrometer reads 3.3 nA leakage; a spec is in µA. Convert to 0.0033 µA to confirm you're within tolerance.

⚡

Power distribution

A feeder is rated 15 kV; an appliance 230 V. Working in a single base unit avoids order-of-magnitude mistakes in load calculations.

🎚️

Audio and signals

Line level is about 1 V; microphone level is a few mV. Converting between them is routine when matching gain stages.

Best Practices for Unit Conversion

  • ✓Pick the prefix closest to your value. Reading 0.000047 A is error-prone; 47 µA is clear. Choosing the natural prefix reduces decimal-point mistakes.
  • ✓Keep one unit system per calculation. Convert everything to a common base — usually volts, amps, ohms, watts — before applying Ohm's Law, then convert the answer back.
  • ✓Watch micro vs milli. µ (micro, 10⁻⁶) and m (milli, 10⁻³) differ by a factor of a thousand and are easy to misread. Double-check the prefix on every datasheet figure.
  • ✓Remember kilo-ohm vs kilowatt share 'k'. The prefix is the same multiplier, but the quantity differs. Make sure you're converting resistance with resistance units, not power.
  • ✓Verify against a known anchor. 1 kΩ = 1,000 Ω and 1 A = 1,000 mA are anchors worth memorising; if a conversion disagrees with one, you've slipped a prefix.

Common Conversion Mistakes

Confusing milli and micro

Treating 4.7 mA as 4.7 µA understates the current a thousandfold — a classic and costly error when sizing components.

Mixing prefixes mid-calculation

Plugging kilo-ohms into a formula expecting ohms gives an answer off by 1,000. Normalise to base units first.

Misplacing the decimal

Manual conversions invite decimal-point slips. Converting 0.0047 A by hand is risky; let the tool shift the decimal for you.

Assuming kV and kW are interchangeable

Both use 'k', but one is voltage and one is power. The prefix scales the same way; the quantity does not.

Why Unit Conversion Matters

Most real electrical errors aren't conceptual — they're unit slips. A milliamp mistaken for an amp, a kilo-ohm read as an ohm, a microvolt confused with a millivolt: each is a factor-of-a-thousand error that can destroy a component or invalidate a measurement. Reliable conversion is the unglamorous foundation of correct electrical work.

Datasheets, meters, schematics, and standards all pick whatever prefix is convenient for them, so the same circuit forces you to move between µA, mA, and A or between Ω, kΩ, and MΩ constantly. A fast, exact converter keeps those translations from becoming the weak link in your design.

Built for electronics hobbyists, technicians, lab staff, and students cross-checking datasheet, meter, and schematic values.

Formulas cross-checked against standard electrical engineering references — see our methodology and editorial policy. Educational only — always confirm critical designs with a licensed electrician and your local electrical code.

Electrical Unit Converter FAQs

Multiply volts by 1,000 to get millivolts, because milli means one-thousandth. So 1.5 V is 1,500 mV, and 0.025 V is 25 mV. To go the other way, divide millivolts by 1,000. This converter does both directions instantly.

Divide milliamps by 1,000 to get amps, since milli is one-thousandth. So 470 mA is 0.47 A, and 20 mA is 0.02 A. To convert amps to milliamps, multiply by 1,000. Pick 'Current' above and the tool shows every prefix at once.

One kilo-ohm (kΩ) is 1,000 ohms, and one mega-ohm (MΩ) is 1,000,000 ohms. So a 4.7 kΩ resistor is 4,700 Ω and a 2.2 MΩ resistor is 2,200,000 Ω. Resistor markings often use the prefix to keep the number short.

Divide watts by 1,000 to get kilowatts. So 1,500 W is 1.5 kW and 750 W is 0.75 kW. To convert milliwatts to watts, divide by 1,000 again — 250 mW is 0.25 W. Select 'Power' above to see all three prefixes together.

Milli (m) means one-thousandth (10⁻³) and micro (µ) means one-millionth (10⁻⁶), so micro is a thousand times smaller than milli. 1 mA equals 1,000 µA. Confusing the two is one of the most common — and most expensive — electrical mistakes.

Prefixes keep numbers readable across an enormous range. A circuit might carry microamps in one branch and amps in another; writing both in plain amps would mean tiny decimals or huge numbers. Prefixes like milli, kilo, micro, and mega scale the unit by powers of ten so the figure stays compact.

Yes — every conversion is a multiply or divide by a power of ten, so no rounding error is introduced beyond the display precision. The tool normalises to the base SI unit and scales out, guaranteeing that 1 kΩ and 1,000 Ω always agree exactly.

Yes. Choose the quantity — voltage, current, resistance, or power — enter a value with its unit, and the converter shows every equivalent prefix. It is part of the Ohm's Law Calculator, so you can convert a value and then use it in a calculation without switching tools.

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