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Current Converter

Instantly convert current with our free converter. See conversion tables, formulas, and step-by-step explanations. Free to use with no signup required.

Reviewed by Manoj Kumar, Mathematics Educator

Reviewed by Manoj Kumar, Mathematics Educator

Formula

I = V / R (Ohm's Law) | Unit Conversion via Ampere base

Current units convert through the ampere (SI base unit). Multiply by the source unit's ampere factor, then divide by the target's factor. Ohm's Law (I = V/R) relates current to voltage and resistance: current in amperes equals voltage in volts divided by resistance in ohms.

Worked Examples

Example 1: LED Circuit Current

Problem:An LED circuit draws 20 mA. Convert to amperes and calculate power at 3.3V.

Solution:Convert: 20 mA x 0.001 A/mA = 0.02 A\nPower = V x I = 3.3V x 0.02A = 0.066W = 66 mW\nThe LED consumes 20 milliamperes = 0.02 amperes and dissipates 66 milliwatts.

Result:20 mA = 0.02 A | Power = 66 mW

Example 2: Industrial Motor Current

Problem:A motor draws 2.5 kA. Express in amperes and milliamperes.

Solution:To amperes: 2.5 kA x 1000 A/kA = 2,500 A\nTo milliamperes: 2,500 A x 1000 mA/A = 2,500,000 mA\nOr directly: 2.5 kA x 1,000,000 mA/kA = 2,500,000 mA

Result:2.5 kA = 2,500 A = 2,500,000 mA

Frequently Asked Questions

What is electric current and what are its units?

Electric current is the flow of electric charge through a conductor, measured in amperes (A). One ampere equals one coulomb of charge passing a point per second. Current is one of the seven SI base units. Common subunits include milliamperes (mA, one thousandth of an ampere) used for small electronics, and microamperes (uA, one millionth) used in sensor circuits. Kiloamperes (kA) measure large industrial currents like those in arc furnaces.

How do I convert between different current units?

All current units relate to the ampere by powers of 10. To convert, multiply the value by the source unit's ampere equivalent, then divide by the target unit's equivalent. For example, to convert 500 mA to amperes: 500 x 0.001 = 0.5 A. To convert 2.5 A to milliamperes: 2.5 / 0.001 = 2,500 mA. The metric prefixes follow standard SI scaling: nano (1e-9), micro (1e-6), milli (1e-3), kilo (1e3), mega (1e6).

What is the relationship between current, voltage, and resistance?

Ohm's Law states that current (I) equals voltage (V) divided by resistance (R): I = V/R. This fundamental relationship governs all resistive circuits. If you know any two values, you can calculate the third. For example, a 12V battery connected to a 100-ohm resistor produces 0.12 A (120 mA) of current. Power dissipated is P = V x I = 12 x 0.12 = 1.44 watts.

References

Reviewed by Manoj Kumar, Mathematics Educator · Editorial policy