# Millivolts to Volts Converter > Convert millivolts (mV) to volts (V) with instant results and common voltage references **Category:** Conversion **Keywords:** millivolts, volts, mv to v, voltage converter, electrical, sensor **URL:** https://complete.tools/millivolts-to-volts ## How it calculates The conversion from millivolts to volts uses a simple division formula: V = mV / 1,000 Where: - mV represents the input voltage in millivolts. - V represents the output voltage in volts, the SI base unit of electrical potential. - The divisor 1,000 reflects the metric prefix "milli-," meaning one-thousandth. For example, to convert 500 millivolts to volts: 500 / 1,000 = 0.5 V. To convert 41 millivolts (a typical thermocouple reading): 41 / 1,000 = 0.041 V. The inverse conversion (volts to millivolts) simply multiplies by 1,000: mV = V x 1,000. This is an exact mathematical relationship defined by the International System of Units (SI). There is no approximation, rounding, or empirical constant involved. The conversion applies equally to DC voltages, AC RMS values, AC peak values, and any other voltage measurement regardless of waveform or frequency. ## Who should use this Instrumentation engineers working with sensors and transducers whose outputs are specified in millivolts but whose data acquisition systems accept inputs calibrated in volts. Thermocouple users who need to convert millivolt readings from thermocouple reference tables into volts for comparison with multimeter or data logger readings displayed in volts. Audio engineers and musicians working with microphone-level signals (typically 1-100 mV) who need to express those levels in volts when calculating preamp gain requirements. Biomedical researchers analyzing EKG, EEG, or EMG recordings where signal amplitudes are measured in millivolts but amplifier specifications and power supply rails are expressed in volts. Electronics hobbyists and students converting between millivolts and volts when building circuits, reading datasheets, or completing coursework involving Ohm's law and Kirchhoff's voltage law calculations. ## Worked examples Example 1: A type K thermocouple reads 41.276 mV at a measured temperature. Converting to volts: 41.276 / 1,000 = 0.041276 V. This matches the voltage that a multimeter set to the volts range would display when measuring the same thermocouple output. Example 2: A strain gauge bridge circuit produces an output of 2.5 mV per volt of excitation. With a 10 V excitation supply, the full-scale output is 25 mV. Converting: 25 / 1,000 = 0.025 V. The data acquisition amplifier must be configured to handle this 25 millivolt full-scale input. Example 3: An ECG machine measures a heart signal with a peak amplitude of 1.2 mV. In volts: 1.2 / 1,000 = 0.0012 V. The amplifier needs a gain of approximately 1,000 to bring this to a 1.2 V signal suitable for analog-to-digital conversion. Example 4: A precision voltage reference outputs exactly 2,500 mV. Converting: 2,500 / 1,000 = 2.5 V. This is a standard reference voltage used in many analog-to-digital converters and calibration systems. ## Limitations This tool performs a pure mathematical conversion and does not interpret what the voltage measurement represents. It does not distinguish between DC, AC RMS, AC peak, or peak-to-peak measurements. The user is responsible for ensuring that the input and output represent the same type of measurement. The converter does not account for measurement uncertainty. A millivolt reading from a sensor has associated accuracy and noise characteristics that are not tracked through the unit conversion. A reading of 41.3 mV from a sensor with 0.5 mV uncertainty should be interpreted as 0.0413 plus or minus 0.0005 V, but the tool does not display error bounds. For voltages below approximately 1 millivolt, the microvolt (uV) unit is more practical and avoids leading zeros in decimal notation. The tool does not automatically suggest switching to microvolts for very small results. The tool assumes numeric input. Non-numeric characters, empty inputs, or special values will not produce a conversion result. ## FAQs **Q:** Why are sensor outputs often expressed in millivolts rather than volts? **A:** Many sensors (thermocouples, strain gauges, pH probes) produce very small electrical signals, typically between 1 mV and 100 mV at full scale. Expressing these in millivolts avoids cumbersome decimal notation like 0.041 V and makes the numbers more intuitive to read, compare, and discuss. The millivolt scale matches the natural magnitude of these signals. **Q:** How many millivolts are in one volt? **A:** There are exactly 1,000 millivolts in one volt. The prefix "milli-" means one-thousandth, so 1 V = 1,000 mV. This relationship is defined by the International System of Units and is exact with no rounding. **Q:** Can I use this to convert negative millivolt values? **A:** The tool accepts positive values for conversion. Negative voltages follow the same mathematical relationship: -500 mV = -0.5 V. The conversion factor of 1,000 applies regardless of the sign of the voltage. **Q:** What is the difference between millivolts and microvolts? **A:** A millivolt (mV) is one-thousandth of a volt, while a microvolt (uV) is one-millionth of a volt. Therefore, 1 mV = 1,000 uV. Microvolts are used for extremely small signals such as EEG brain waves, antenna signals, and noise-floor measurements, while millivolts cover the range of most sensor outputs and low-level analog signals. **Q:** Is the millivolt-to-volt conversion the same for AC and DC? **A:** Yes, the mathematical conversion is identical. Dividing by 1,000 applies regardless of whether the signal is AC or DC. However, for AC signals, make sure you are consistent about whether you are working with RMS, peak, or peak-to-peak values, since each represents a different number for the same waveform. --- *Generated from [complete.tools/millivolts-to-volts](https://complete.tools/millivolts-to-volts)*