Electric Current Converter
0.25A
1 mA = 0.001 A exact
- 250 x 0.001 0.25 ampere
In every electric current unit
| Unit | Value |
|---|---|
| microamperes | 250000 uA |
| milliamperes | 250 mA |
| amperes | 0.25 A |
| kiloamperes | 0.00025 kA |
This page converts an electric current from one unit into another. Every value passes through the ampere, the SI unit electric current is held in, and electric current stays electric current: a unit only converts inside its own dimension.
How do you convert an electric current between amps, milliamps and kiloamps?
Pick the unit you have, pick the unit you want, and type the value. The page multiplies by the factor between the two and prints the arithmetic under the result, so the answer and the working are the same object.
- Choose the unit your value is in. This page opens on the milliampere.
- Choose the unit you want it in. This page opens on the ampere.
- Type the value, or the value with its units, such as 250 mA to A. The result and the factor behind it appear together.
- Read the working. It converts into the ampere first and out again, which is the same two lines you would write by hand.
Amps, milliamps and kiloamps measure current only, so for volts, amp-hours or VA, pick the matching quantity on the electrical unit converter.
Electric Current Conversion Table
One row per unit this page offers, each measured against the ampere. The last column says whether the factor is a definition or a reading of one.
| Unit | Symbol | In the SI unit | Exact? |
|---|---|---|---|
| microampere | uA | 0.000001 | exact |
| milliampere | mA | 0.001 | exact |
| ampere | A | 1 | exact |
| kiloampere | kA | 1000 | exact |
Worked Examples
The question the bank ranked highest for this page, answered with the working.
Where These Factors Come From
Every factor above is read from the knowledge base rather than typed for the page, and every result is worked from those factors. These are the statements it holds for electric current.
- The ampere is an SI base unit. Since 2019 it has been fixed by defining the elementary charge as exactly 1.602176634 x 10^-19 C, so one ampere is one coulomb per second.
- elementary charge, value 1.602176634 x 10^-19
- An SI prefix multiplies a unit by a power of ten: k is 10^3, M is 10^6, G is 10^9, m is 10^-3, micro is 10^-6 and n is 10^-9. The prefix belongs to the unit, so 1 kV is 1000 V.
- How this page reports a result result in the target ampere prefix, plain decimal
SI prefixes on this page
| Prefix | Symbol | Factor |
|---|---|---|
| kilo | k | 10^3 |
| milli | m | 10^-3 |
| micro | u | 10^-6 |
What Does the Prefix Change?
An SI prefix multiplies the ampere by a power of ten and changes nothing else. The quantity, the dimension and the reading stay the same; the only thing that has moved is the size of the unit the number is counted in.
- A larger prefix gives a smaller number for the same current. If the figure grew when the prefix grew, the factor was applied the wrong way up.
The rule behind this factor is the same for every unit - what k, M and m multiply by.
Frequently Asked Questions
How many milliamps are in an amp?
1000 mA.
What is a microamp?
One millionth of an ampere, 10^-6 A.
Is the ampere an SI base unit?
Yes. Since 2019 it is fixed by defining the elementary charge as exactly 1.602176634 x 10^-19 C.
What is the difference between amps and amp-hours?
An amp measures current, the rate of flow. An amp-hour measures charge, the amount that has flowed, and belongs on the charge converter.
Related Conversions
The rest of the family sits on the electrical unit index.