Convert Current from Milliamperes (mA) to other units

Milliampere Conversion Formulas

Milliampere to Ampere Conversion Formula

Milliampere to Microampere Conversion Formula

Milliampere to Kiloampere Conversion Formula

Milliampere to Megaampere Conversion Formula

What is a Milliampere (mA)?

A milliampere (mA) is a crucial unit used to measure small amounts of electrical current.

Think of electrical current like the flow of water through a pipe. If a large pipe represents an ampere (A)—the standard unit for current—then a milliampere would be the tiny trickle of water flowing through a drinking straw.

It is part of the International System of Units (SI) and is equal to one-thousandth of an ampere.

1 A = 1,000 mA.

How is a Milliampere Defined?

The milliampere is a standard submultiple of the ampere, the base unit for electrical current.

The prefix "milli" signifies one-thousandth (10^-3).

This standardized measurement ensures that engineers, scientists, and technicians worldwide are using consistent values for measuring electricity.

What Are Milliamperes Used For?

Because a milliampere represents a very small amount of current, it is the perfect unit for measuring the power consumption of everyday small electronics.

You'll see mA used to describe the electricity needed for:

• LED lights: The tiny indicator lights on your TV or computer modem.
• Sensors: Components inside devices that detect things like light, motion, or temperature.
• Microcontrollers: The mini-computers that run your smart appliances and other devices.
• Smartphone Batteries: You've likely seen your phone battery capacity listed in milliampere-hours (mAh). This critical unit tells you how much electrical current the battery can provide over a specific period. For example, a 5,000 mAh battery can supply 5,000 milliamperes of current for one hour.

Why Milliamperes Decide Electrical Safety

Electrical injury is governed by current through the body, not by voltage — which is why safety literature is written in milliamperes.

The commonly cited thresholds for a 50/60 Hz current passing hand-to-hand through an adult are:

• About 1 mA — the threshold of perception, felt as a faint tingle.
• 5–10 mA — painful shock; muscles begin to react involuntarily.
• 10–20 mA — the let-go threshold. Above it, forearm muscles contract hard enough that the victim cannot release the conductor, which is what turns a brief contact into a sustained one.
• Above roughly 100 mA — current through the chest can trigger ventricular fibrillation, the mechanism behind most electrocution deaths.

The numbers explain a detail that often looks strange: a residual-current device (RCD or GFCI) trips at just 30 mA in Europe or 5 mA in North America. Those settings sit deliberately below the fibrillation range, not below the level at which a shock hurts. The device is not there to prevent a shock — it is there to cut the circuit before that shock becomes fatal.

The 4–20 mA Current Loop

Industrial instrumentation transmits measurements as a current between 4 and 20 mA rather than as a voltage, and the choice is deliberate.

Current is identical at every point in a series loop, so voltage drop along a long cable run — which would corrupt a voltage signal — has no effect on the reading. The live zero at 4 mA is equally purposeful: a healthy sensor reading its minimum still draws 4 mA, so a reading of 0 mA can only mean a broken wire or dead transmitter. A 0–20 mA scheme could not distinguish "minimum value" from "cable cut".