# Ampere vs. Milliampere — What's the Difference?

Edited by Tayyaba Rehman — By Fiza Rafique — Updated on May 14, 2024

**An ampere (A) is the standard unit of electric current in the International System of Units, representing a substantial flow of electric charge. A milliampere (mA) is a smaller unit, equivalent to one-thousandth of an ampere, used for smaller currents.**

## Difference Between Ampere and Milliampere

### Table of Contents

ADVERTISEMENT

## Key Differences

The ampere, commonly abbreviated as A, measures larger currents such as those in household appliances and industrial equipment, while the milliampere, abbreviated as mA, measures smaller currents, typical in electronic devices like smartphones and sensors.

One ampere represents the flow of one coulomb of charge per second, indicating significant electrical activity, whereas one milliampere is just 0.001 amperes, indicating much less electrical activity.

In practical applications, devices such as circuit breakers and electrical wiring are often rated in amperes, reflecting their capacity to handle heavier electrical loads, whereas milliamperes are more common in the specifications of low-power devices.

Amperes are essential for describing the electrical capacity of larger systems like the electrical grid or major appliances, whereas milliamperes are crucial for understanding the delicate electronics in gadgets and microcontrollers.

Calculations involving electrical power in households or industrial settings often use amperes to determine potential loads and energy consumption, while milliamperes are frequently used in calculations involving battery life in portable electronics.

ADVERTISEMENT

## Comparison Chart

### Definition

Unit of electric current equal to one coulomb per second.

One-thousandth of an ampere.

### Typical Use

Used for household appliances, industrial equipment.

Used in small electronic devices, sensors.

### Electrical Activity

Indicates significant electrical current flow.

Indicates minimal electrical current flow.

### Application Examples

Circuit breakers, wiring ratings, large motors.

Smartphones, PCBs, small sensors.

### Measurement Scale

Larger scale for more substantial electrical flows.

Smaller scale for precise, low-current applications.

## Compare with Definitions

#### Ampere

It is used to measure the electrical usage of large devices.

An electric stove may use about 30 amperes.

#### Milliampere

A milliampere is a unit of electric current used to measure very small currents, useful in precision electronics.

A typical LED operates at about 20 milliamperes.

#### Ampere

An ampere is a unit of electric current representing the flow of electrical charges through a conductor.

A standard household circuit operates at about 15 to 20 amperes.

#### Milliampere

Common in specifications for electronic components.

The current consumption of a microcontroller might be just a few milliamperes.

#### Ampere

Used in describing the capacity of electrical systems.

A residential electrical service panel might be rated for 100 amperes.

#### Milliampere

Used in medical devices that require precision.

Portable medical sensors use milliamperes to ensure safety and functionality.

#### Ampere

Amperes help in calculating electrical load in wiring and safety devices.

The size of the circuit breaker is determined by the maximum current, measured in amperes, it needs to handle.

#### Milliampere

Crucial for battery-powered devices to determine battery life.

A smartphone battery capacity is often described in terms of milliamperes-hour.

#### Ampere

Key in industrial applications where high power is required.

Industrial motors often require several hundred amperes for operation.

#### Milliampere

Important in the context of energy-saving technology.

Modern energy-efficient lighting solutions often operate at low milliampere levels.

#### Ampere

The ampere (, US: ; symbol: A), often shortened to amp, is the base unit of electric current in the International System of Units (SI). It is named after André-Marie Ampère (1775–1836), French mathematician and physicist, considered the father of electromagnetism.

#### Milliampere

A unit of current equal to one thousandth (10-3) of an ampere.

#### Ampere

The basic unit of electric current, equal to one coulomb per second and equivalent to the current, flowing in two straight parallel wires of negligible cross section separated by a distance of one meter, that produces a force between the wires of 2.0 × 10-7 newtons per meter of length. The value of an ampere in the International System differs very slightly from that in the meter-kilogram-second-ampere system of units. See Table at measurement.

#### Milliampere

One thousandth (10

^{-3}) of an ampere.#### Ampere

A unit of electrical current, the standard base unit in the International System of Units; colloquially amp. Abbreviation: amp, Symbol: A

Definition: The ampere, symbol A, is the SI unit of electric current. It is defined by taking the fixed numerical value of the elementary charge e to be 1.602

X 10

^{−19}when expressed in the unit C, which is equal to AS, where the second is defined in terms of Δν

_{Cs}. ([https://www.bipm.org/en/si-base-units/ampere The International Bureau of Weights and Measures])#### Milliampere

The thousandth part of one ampère.

#### Ampere

The unit of electric current; - defined by the International Electrical Congress in 1893 and by U. S. Statute as, one tenth of the unit of current of the C. G. S. system of electro-magnetic units, or the practical equivalent of the unvarying current which, when passed through a standard solution of nitrate of silver in water, deposits silver at the rate of 0.001118 grams per second. Called also the international ampère.

#### Milliampere

One thousandth of an ampere

#### Ampere

A former unit of electric current (slightly smaller than the SI ampere)

#### Ampere

The basic unit of electric current adopted under the Systeme International d'Unites;

A typical household circuit carries 15 to 50 amps

## Common Curiosities

#### Can the use of amperes and milliamperes affect device performance?

Yes, the incorrect calculation of current needs in amperes or milliamperes can lead to overheating, insufficient power supply, or even device failure.

#### What is the relationship between amperes and voltage in an electrical system?

In an electrical system, amperes and voltage are related by Ohm’s Law, where the current in amperes equals the voltage divided by resistance, showing how changes in voltage or resistance will affect the current.

#### What does one ampere represent in physical terms?

One ampere represents the flow of one coulomb of electric charge per second.

#### How does the measurement of amperes impact electrical safety?

Measuring and understanding amperes is vital for electrical safety as it helps in selecting the correct wiring and safety devices like fuses and circuit breakers to prevent electrical fires and failures.

#### What applications typically require the use of amperes?

Applications that require significant power, such as air conditioning units, large electric motors, and entire household electrical systems, typically measure current in amperes.

#### Why are milliamperes important in modern electronics?

Milliamperes are crucial for measuring the small currents that modern, low-power electronic devices and circuits use, which is essential for efficiency and battery management.

#### What devices typically use milliamperes?

Devices like watches, calculators, smartphones, and other portable electronics typically use milliamperes because they require much less power.

#### How do you convert amperes to milliamperes?

To convert amperes to milliamperes, multiply the number of amperes by 1,000. For example, 2 amperes equal 2,000 milliamperes.

#### Can an incorrect measurement in milliamperes impact device efficiency?

Yes, incorrect measurements or estimations in milliamperes can lead to poor battery performance, reduced device efficiency, and potential harm to sensitive electronics.

#### Why is it important to know the current in amperes for home appliances?

Knowing the current in amperes for home appliances is crucial for safety and functionality, ensuring that the electrical infrastructure can handle the appliance without risk of overload or electrical fires.

#### What is the practical importance of milliamperes in battery life calculations?

Milliamperes are critical in battery life calculations as they help predict how long a device can operate on a single charge, influencing design and usage guidelines for battery-operated devices.

## Share Your Discovery

Previous Comparison

Delegitimate vs. LegitimateNext Comparison

Iatrogenic vs. Idiopathic## Author Spotlight

Written by

Fiza RafiqueFiza Rafique is a skilled content writer at AskDifference.com, where she meticulously refines and enhances written pieces. Drawing from her vast editorial expertise, Fiza ensures clarity, accuracy, and precision in every article. Passionate about language, she continually seeks to elevate the quality of content for readers worldwide.

Edited by

Tayyaba RehmanTayyaba Rehman is a distinguished writer, currently serving as a primary contributor to askdifference.com. As a researcher in semantics and etymology, Tayyaba's passion for the complexity of languages and their distinctions has found a perfect home on the platform. Tayyaba delves into the intricacies of language, distinguishing between commonly confused words and phrases, thereby providing clarity for readers worldwide.