Enter a value in any field to convert between all units
Visual representation of current magnitude
Note: The meter shows relative magnitude on a logarithmic scale.
Compare different current magnitudes across common applications
| Current Range | Example Applications | Typical Units |
|---|---|---|
| 1 pA - 1 nA | Semiconductor leakage currents, sensitive scientific instruments | pA |
| 1 nA - 1 μA | Photodiodes, ion chambers, precision sensors | nA |
| 1 μA - 1 mA | Low-power electronics, microcontroller sleep modes, small LEDs | μA |
| 1 mA - 100 mA | IoT devices, sensors, small motors, standard LEDs | mA |
| 100 mA - 10 A | Household appliances, power tools, laptop chargers | A |
| 10 A - 1 kA | Electric vehicles, industrial equipment, large motors | A |
| 1 kA - 100 kA | Power distribution, industrial welding, lightning strikes | kA |
| 100 kA - 1 MA | High-voltage transmission lines, large industrial systems | kA, MA |
Calculate current using Ohm's Law and Power equations
Understanding electric current in various fields and industries
In electronics, current is typically measured in microamperes (μA) to amperes (A). For example:
Understanding current requirements is essential for designing power supplies, battery management systems, and ensuring components operate within safe limits.
Industrial settings often deal with much larger currents, measured in amperes (A) to kiloamperes (kA):
Safety measures and proper conductor sizing are critical when working with such high currents to prevent equipment damage and ensure personnel safety.
Power distribution systems handle some of the largest currents in everyday applications:
Current calculations are essential for sizing conductors, specifying protection devices, and ensuring efficient power delivery.
Scientific applications often measure extremely small currents:
These applications require highly sensitive equipment and careful shielding from electromagnetic interference.
Electric current is the flow of electric charge through a conductor, measured in amperes (A). One ampere represents one coulomb of charge passing a point in one second.
The SI unit of electric current is the ampere (A), which is one of the seven base units in the International System of Units. For practical applications, we use various multiples and submultiples of the ampere:
Current spans a similarly wide range, and the unit in use is usually a good clue to the application.
Worth remembering: it is current, not voltage, that sets conductor size and causes heating, and the relationship is quadratic. Doubling current quadruples the I2R loss in every connection it passes through.
| Prefix | Symbol | Factor |
|---|---|---|
| pico | p | 10−12 |
| nano | n | 10−9 |
| micro | µ | 10−6 |
| milli | m | 10−3 |
| kilo | k | 103 |
| mega | M | 106 |
| giga | G | 109 |
Two conventions cause real errors. Case matters: m is milli and M is mega, a factor of a billion apart, so writing mW when MW is meant is not a typo anyone can shrug off. And µ is frequently written as u because it is easier to type — 10uF and 10µF mean the same thing, and the substitution is universal enough in datasheets and schematics to be treated as standard.
Engineering notation — exponents restricted to multiples of three — exists precisely so that every value maps onto a prefix. It is why components are specified as 4.7 kΩ rather than 0.0047 MΩ, and why keeping values in that form makes mental arithmetic and cross-checking far easier.
About 8.8 mAh over a year. That is why careful sleep-mode design allows battery-powered equipment to run for a decade on a single cell.
The current that would flow in a short circuit at a given point, determined by the supply impedance. Protective devices must be able to interrupt it safely, which is what their breaking capacity rating describes.
m is milli, meaning one thousandth, and M is mega, meaning one million. They differ by a factor of a billion, so case must be written carefully.
Because µ is awkward to type on many keyboards and did not survive older character encodings. Writing 10uF for 10µF is standard practice in datasheets and schematics.
Scientific notation restricted to exponents that are multiples of three, so that every value corresponds to an SI prefix. It is why components are quoted as 4.7 kΩ rather than 0.0047 MΩ.