Current Converter

What is electric current and how is it measured?

While voltage acts as the pressure pushing electrons, electric current is the actual flow rate of those electrons. Imagine water flowing through a garden hose—the amount of water passing through a point in the hose per second represents the current. In electronics, we measure current in Amperes (A), named after André-Marie Ampère. One Ampere represents one Coulomb of charge (which is about 6.242 × 10¹⁸ electrons) passing through a point in a circuit every second.

Common current scales: Milliamperes and Microamperes

Most everyday gadgets and microcontrollers (like Arduinos or smartphones) operate on small amounts of current. They draw current inmilliamperes (mA) or even microamperes (µA) when in sleep mode. For example, a typical USB port supplies up to 500mA or 900mA, and a simple LED light needs about 20mA to run. Conversely, heavy machinery, power stations, and industrial welders consume electricity in kiloamperes (kA). Bouncing between these scales lets you calculate battery life and wire thickness requirements easily.

Scientific units: Biot, Abampere, and Statampere

Before standard SI metric was adopted globally, electromagnetic units were defined in the CGS electromagnetic system. The CGS unit for current is the Biot (Bi), which is named after Jean-Baptiste Biot and is equal to exactly 10 Amperes. It is also referred to as the abampere. In the companion CGS electrostatic system, current is measured in statamperes. One statampere is incredibly small, equal to approximately 3.3356 × 10^-10 Amperes. It is derived from the electrostatic charge unit flowing per second, and is still useful when calculating electrostatic fields or modeling molecular-level physics.