Enter the temperature (°C or °F) or the sensor output voltage (mV or V) into the calculator to determine the missing variable. This calculator uses the common TMP36-style linear relationship (500 mV offset at 0°C and 10 mV/°C slope), not a thermocouple table/polynomial conversion.
Mv to Temperature Formula
The following formula is used to calculate temperature for a given voltage reading for common linear analog sensors (such as the TMP36).
T = (V - 0.5) * 100 T = (mV - 500) / 10
Variables:
- T is the temperature in Celsius (°C)
- V is the sensor output voltage in volts (V)
- mV is the sensor output voltage in millivolts (mV)
To calculate the temperature, subtract 0.5 V (or 500 mV) from the voltage reading and then multiply by 100 (if using volts) or divide by 10 (if using millivolts).
| Voltage (V) | Millivolts (mV) | Temperature (°C) | Temperature (°F) |
|---|---|---|---|
| 0.10 | 100 | -40 | -40 |
| 0.30 | 300 | -20 | -4 |
| 0.40 | 400 | -10 | 14 |
| 0.50 | 500 | 0 | 32 |
| 0.55 | 550 | 5 | 41 |
| 0.60 | 600 | 10 | 50 |
| 0.65 | 650 | 15 | 59 |
| 0.70 | 700 | 20 | 68 |
| 0.75 | 750 | 25 | 77 |
| 0.80 | 800 | 30 | 86 |
| 0.85 | 850 | 35 | 95 |
| 0.90 | 900 | 40 | 104 |
| 1.00 | 1000 | 50 | 122 |
| 1.10 | 1100 | 60 | 140 |
| 1.20 | 1200 | 70 | 158 |
| 1.30 | 1300 | 80 | 176 |
| 1.40 | 1400 | 90 | 194 |
| 1.50 | 1500 | 100 | 212 |
| 1.60 | 1600 | 110 | 230 |
| 1.70 | 1700 | 120 | 248 |
| * Rounded as shown. Assumes T(°C) = (V − 0.5) × 100 (equivalently T(°C) = (mV − 500) ÷ 10), 1 V = 1000 mV, and °F = (°C × 9/5) + 32. | |||
What is a Millivolt to Temperature Conversion?
A millivolt to temperature conversion is a method used to estimate temperature from the voltage output of a temperature sensor. Some sensors (such as the TMP36) have an approximately linear voltage output with a defined offset and slope (about 500 mV at 0°C and 10 mV per °C), making conversion straightforward using a simple formula.
Note: thermocouples also produce a small voltage, but their voltage-to-temperature relationship is not the simple linear-offset formula used here and depends on thermocouple type and cold-junction compensation.
How to Calculate Temperature from Millivolts?
The following steps outline how to calculate the temperature from millivolts (for TMP36-style linear sensors).
- First, obtain the voltage reading from the temperature sensor.
- If your reading is in millivolts, subtract 500 mV (equivalently subtract 0.5 V if using volts).
- Divide the result by 10 to get the temperature in Celsius (equivalently, if using volts: multiply (V − 0.5) by 100).
- After inserting the values and calculating the result, check your answer with the calculator above.
Example Problem :
Use the following variables as an example problem to test your knowledge.
Millivolt value (mV) = 1200
Temperature (T) = (1200 − 500) / 10 = 70°C