Milliampere is 0.001 ampere units.
Milliamperes to Amperes Converter — mA to A
Convert Milliampere (mA) to Ampere (A) using the exact conversion factor (1 milliampere = 0.001 ampere). See the formula, worked examples, conversion table, history, and common uses.
Milliamperes to Amperes converter
Converter
Electricity Converter
Convert electrical units by family and calculate voltage, current, resistance, power, and energy with context values.
Context values
Some unit families need one extra value for a physically accurate result.
Ampere is the SI unit of electric current.
Result = input x 0.001 / 1.
Electrical units in the same family convert directly.
Reserved above the conversion cards and below the converter.
About Converting Milliamperes to Amperes
Milliampere and Ampere both belong to the electricity family — voltage, current, resistance, power, or energy — units that show up constantly when working across the different standards used by household wiring (120V/240V depending on region), automotive electrical systems (12V/24V), and electronics design. Specifically: Milliampere is 0.001 ampere units, and ampere is the SI unit of electric current.
Formula
amperes = milliamperes × 0.001
This factor comes from each unit's defined relationship to the category's base unit: 1 milliampere equals 0.001 base units, and 1 ampere equals 1 base unit, so dividing one by the other gives the direct milliampere-to-ampere factor of 0.001.
Simple example
1 mA × 0.001 = 0.001 A
1 milliampere = 0.001 amperes.
Real-world example
120 mA × 0.001 = 0.12 A
120 milliamperes = 0.12 amperes.
Conversion table
| Milliampere (mA) | Ampere (A) |
|---|---|
| 1 mA | 0.001 A |
| 5 mA | 0.005 A |
| 12 mA | 0.012 A |
| 24 mA | 0.024 A |
| 120 mA | 0.12 A |
| 240 mA | 0.24 A |
Reverse conversion: Ampere to Milliampere
0.001 A × 1000 = 1 mA
0.001 amperes = 1 milliampere.
milliamperes = amperes × 1000
For a page dedicated to this direction, see Ampere to Milliampere.
Understanding the Milliampere (mA)
Milliampere is 0.001 ampere units.
Understanding the Ampere
Ampere (A) measures electric current. The SI base unit of electric current. It is classified as a SI base unit.
Where it's used: Universal — SI base unit used worldwide
Uses of the Ampere today
- Electrical circuit design and fuse/breaker ratings
- Battery and charger current specifications
- Motor and appliance current draw ratings
History of the Ampere
The ampere is named after André-Marie Ampère (1775–1836), a French physicist and mathematician regarded as one of the founders of classical electromagnetism, for his early work relating electric current to magnetic force.
Originally defined via the force between two parallel current-carrying wires, the ampere was redefined on 20 May 2019 by fixing the elementary charge at exactly 1.602176634 × 10⁻¹⁹ coulombs, so it can now be realized without reference to a specific physical apparatus.
Historical origin. Ampere was not the invention of a single named person; it developed through the process described above.
Ampere — sources
- BIPM SI Brochure, 9th edition — Official definition of the ampere since the 2019 redefinition.
Reserved between the cards and the FAQ so the page stays balanced.
Frequently asked questions
How many amperes are in 1 milliampere?
1 milliampere equals 0.001 amperes, using the exact defined conversion factor rather than an estimate.
How do I convert milliampere to ampere?
Multiply the milliampere value by 0.001. The converter above does this instantly to whatever precision you set.
How do I convert ampere back to milliampere?
Use the reverse factor: 1 ampere equals 1,000 milliamperes. You can also use the swap control in the converter above to flip the direction instantly.
What is a milliampere?
Milliampere (mA) is a unit of electricity.
What is a ampere?
Ampere (A) measures electric current. The SI base unit of electric current. It is classified as a SI base unit.
Is the milliampere to ampere conversion exact?
Yes. Both milliampere and ampere are defined by fixed standards rather than physical artifacts, so the factor of 0.001 used above is exact to as many digits as you choose to display.
What's the difference between voltage, current, and resistance?
Voltage (volts) is the electrical potential difference driving current through a circuit. Current (amperes) is the rate of flow of electric charge. Resistance (ohms) is how much a component opposes that flow. They're related by Ohm's law (V = I × R), but they are distinct physical quantities, and this page converts between units of just one of them.