Current Converter
A comprehensive tool to convert between various electrical current units like Amperes, Milliamperes, and more.
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About this tool
Convert electric current between ampere (A), milliampere (mA), microampere (µA), nanoampere (nA), kiloampere (kA), megaampere (MA), gigaampere (GA) and the older CGS units statampere (statA) and abampere (abA, 10 amperes). The menus show full names with symbols, and the result is labeled with the symbol, so milliampere (mA) and megaampere (MA) are easy to tell apart. Phone chargers and LED circuits typically use mA, sensors use µA, and lightning or welding can reach kA. Everything converts through amperes, and results show up to 8 decimals.
How to use it
- Type the value to convert.
- Choose the From and To units.
- Read the result, which updates as you type.
- Use Swap to reverse the units or Copy to copy the result.
Example
250 milliampere to ampere
0.25 A
Current units in amperes
- 1 mA (milliampere)
- 0.001 A. Multiply amps by 1,000 to get milliamps.
- 1 µA (microampere)
- 0.000001 A, or 0.001 mA.
- 1 nA (nanoampere)
- 0.000000001 A, or 0.001 µA.
- 1 kA (kiloampere)
- 1,000 A.
- 1 abA (abampere)
- 10 A, the CGS electromagnetic unit.
- 1 statA (statampere)
- about 3.33564 x 10^-10 A, the CGS electrostatic unit.
Working out current from power, voltage or resistance
Unit conversion only changes the scale. To find the current itself, use power and voltage, or voltage and resistance. Use the Ohm's Law Calculator to solve these from any two values.
I = P / V 60 W at 12 V = 5 A = 5000 mA I = V / R 5 V across 250 ohm = 0.02 A = 20 mA
Battery capacity in mAh
A battery's mAh rating is current multiplied by time. Dividing capacity by the current drawn gives a rough runtime: 2,000 mAh at 200 mA is about 10 hours. Real runtime is usually shorter, because capacity drops with high current, low temperature and age.
Common problems
- Milli or mega?
- Milliampere (mA) is 1/1000 A and megaampere (MA) is 1,000,000 A. The capital M in the result label means mega.
- Tiny results shown in exponent form
- Very small values use scientific notation. Convert to µA or nA for a plain number.
- Statampere and abampere
- These are legacy CGS units rarely used in practice, so the results are mainly for physics reference.
Frequently asked questions
How many milliamps are in an amp?
1,000. So 0.5 A is 500 mA and 2,500 mA is 2.5 A.
Can this convert amps to watts?
No. Watts are a different quantity and need the voltage: watts = volts x amps. The Ohm's Law Calculator does that.
Can it convert a temperature to a 4-20 mA signal?
No. A 4-20 mA transmitter maps its range linearly, so you can work it out by hand: mA = 4 + 16 x (T - Tmin) / (Tmax - Tmin). For a 0-100 °C range, 25 °C gives 8 mA.