You can measure millivolts with some voltmeters and multimeters. A voltmeter measures voltage. A multimeter can measure multiple quantities, such as voltage (volts), resistance (ohms) and current (amperes). Meters can be digital or analog. A millivolt is equal to one thousandth of a volt. Make sure your meter has the ability to measure into the millivolt range.

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Millivolts can be measured with a voltmeter.

Step 1

Plug the red probe into the hole marked "V" or "+" on your meter. The hole may be colored red.

Step 2

Plug the black probe into the hole marked "COM" or "-" on your meter. The hole may be colored black.

Step 3

Turn the dial on your meter to a milivolt range setting. The setting should be close to but not over the maximum voltage you are measuring. Use the DCV settings if you are measuring a direct current (DC) source, such as a battery. Use the ACV settings to measure alternating current (AC) sources, such as house appliances.

Step 4

Turn your meter on.

Step 5

Hold the insulated handles of your probes. Touch the red probe to the positive (+) side of your DC or AC circuit. Touch the black probe to the negative (-) side of the circuit.

Step 6

Read the measurement from the meter dial or the display screen.