Calibration of thermometer Xiaomi: how to adjust the exact readings in 5 minutes

Xiaomi’s high-tech thermometers are among the most popular smart thermometers on the market due to their combination of precision, compactness and integration with the Mi Home ecosystem. However, even high-tech devices can give you errors over time: the contactless Mi Thermometer 2 shows the latest in the series. +0.3°C to real temperature, and the built-in sensor in the Mi Band 7 overstates the data after a year of use, for reasons ranging from factory defects to natural wear and tear on the sensors. In this article, we will discuss how to independently calibrate the thermometer Xiaomi of different models to return it to factory accuracy or even improve it.

It's important to understand that calibration doesn't always solve the problem: if the device fell from a height, came into contact with water (for leaky models), or was operated at extreme temperatures (below). -10°C or higher +50°C), may require repair or replacement. 80% In cases where the error is eliminated by software methods or simple manipulation of settings. We will look at the official methods from the manufacturer, hidden functions of the Mi application. Fit/Zepp Life, as well as “folk” methods for emergency reading adjustment.

What Xiaomi Thermometers Can Be Calibrated By Yourself

Not all Xiaomi thermometers support manual calibration, and the ability to adjust depends on the model, firmware version, and sensor type.

Note that Xiaomi’s contactless thermometers (such as Mi Thermometer 2) are calibrated differently than fitness bracelets. The former require a reference, such as a medical mercury thermometer or a professional pyrometer, while the latter are adjusted through the application algorithms. If your model does not make it into the table, check its name in documents or on the box – often under the Xiaomi brand, sub-brand devices (Aqara, Mijia) are sold, which have their own nuances of settings.

Preparation for calibration: what will be needed

Before you start setting up, prepare:

• 📱 Smartphone with Mi Home app installed (for thermometers) or Mi Fit/Zepp Life (for fitness bracelets) The software version should be at least lower 6.0.100 for Mi Home and 5.6.0 for Mi Fit.
• 🔋 Charged device (at least 30% battery).For Mi Thermometer 2, the charge level is critical - at a discharge below 15%, the sensor can give an error of up to ±0.5°C.
• 🌡️ Reference thermometer (for contactless models) A certified medical thermometer with a margin of error of no more than ±0.1°C. No standard is required for Mi Band calibration.
• 📡 Stable Internet connection: Some models (e.g. Aqara Temperature Sensor) require cloud sync to save settings.

An important caveat: if you calibrate a non-contact thermometer, use a reference thermometer of the same type (infrared), and it's pointless to compare the readings of a contact and non-contact thermometers, because their working principles are fundamentally different. For example, Mi Thermometer 2 measures surface temperature rather than internal body temperature, so it’s best to use a glass of water of a known temperature to check for accuracy (e.g., melting ice). = 0°C).

⚠️ Note: Do not calibrate immediately after the device is turned on. Xiaomi sensors take 10-15 minutes to stabilize the readings, especially after a temperature drop (for example, if you bring a thermometer from the street into a warm room).

Calibration of the contactless thermometer Mi Thermometer 2

Model Mi Thermometer 2 (LYWSD03MMC) — It's one of the most popular, but also the most capricious, in terms of accuracy. ±0.1°C, but in practice it often achieves ±0.3–0.5°C. This can be corrected through the hidden calibration menu in the Mi Home app.

Step-by-step:

1. Open Mi Home and select your thermometer from the device list.
2. Go to Settings. → Additionally. → Calibration of the sensor (the item may be called Correction in the English version).
3. In the Temperature Offset field, enter the adjustment value, for example, if the thermometer overstates the value of the adjustment. 0.3°C, point out -0.3.
4. Press Save and wait for sync (the cloud icon in the upper right corner should stop spinning).

Critical detail: once calibrated, the thermometer needs to be rebooted, so take the battery out for 10 seconds, then insert it back in, and without rebooting, the changes may not take effect.

If the sensor calibration item is not in the menu, try:

• 🔄 Update thermometer firmware through Mi Home → Device profile → Update of the PO.
• 📲 Switch the region to Mi Home to China (Mainland China) – more features in the Chinese version of the application.
• 🔧 Use alternative software, such as Aqara Home or Home Assistant (requires customization skills).

Prepare a reference thermometer|Check the battery charge (>30%)|Update Mi Home to the latest version|Compare readings under the same conditions|Insert correction in settings|Reset the device-->

Temperature adjustment in Mi Band and Mi Watch

Xiaomi fitness bracelets (Mi Band and Mi Watch series) measure skin temperature, not body temperature, so their readings will always be below the “classic” 36.6°C. However, if the difference is greater than 1-1.5°C or data jumps for no reason, adjustments are required.

Method 1: Resetting sensor settings

The most reliable method is to reset the temperature sensor settings through the engineering menu:

1. In the Mi Fit or Zepp Life app, go to your device profile.
2. Click on the gear icon (Settings) → Additionally. → Sensor reset.
3. Confirm the reset and wait for the bracelet to restart (it will take). ~2 minutes).

Method 2: Manual adjustment in Zepp Life

Zepp Life app for Mi Band 7/8 Mi Watch allows for the amendment:

1. Open Zepp Life. → Profile → The device → Temperature settings.
2. Activate the option to correct the readings.
3. Enter the displacement value (for example, +0.5 if the bracelet lowers the temperature).

⚠️ Warning: After the sensors are reset, the bracelet will take 24 to 48 hours to "train" and stabilize the readings, during which time the data may be inaccurate - this is normal.

If both methods failed, the problem may lie in poor contact of the sensor with the skin.

• 💍 Density of the adhesive bracelet (should sit tight, but not crush blood vessels).
• 🧼 Sensor cleanliness (wipe with an alcohol napkin).
• 🔋 Charge level (at a discharge below 20% temperature sensor is turned off).

💡

For accurate measurements of body temperature with the Mi Band, wear a wristband on the wrist of the non-working hand (left for right-handers, right for left-handers), and blood flow is more stable, which reduces the error.

Calibration of the environmental sensor in smart watches

Xiaomi smartwatches (such as Mi Watch or Watch) S1) They're equipped with ambient temperature sensor, which is often used for weather forecasting or microclimate monitoring, and its calibration is different from medical thermometers and requires a special approach.

Algorithm of action:

1. Place the watch next to the reference thermometer (for example, room thermometer) in stable conditions (without drafts, direct sunlight).
2. Wait for the synchronization of the readings (10-15 minutes).
3. In the Mi Fit app, go to the Device Profile → Settings → Sensors. → Ambient temperature.
4. Press Calibration and enter the difference between the reference and current value.

For models with Amazon Alexa or Google Assistant support (e.g. Xiaomi Watch) S1 Pro) the calibration can be done by voice:

"Alexa, calibrate the temperature sensor 0.2 degrees up."

If voice commands are not supported, use an alternative method through Home Assistant:

Frequent Mistakes and How to Avoid Them

Even with proper calibration, users often encounter problems, and here are the most common errors and solutions:

Another common mistake is calibration in unstable conditions, for example, if you set up the Mi Thermometer 2 outdoors in the wind or in direct sunlight, the sensor will respond to external factors rather than the actual temperature of the object.

• 🏠 Closed room without drafts.
• 🌡️ Air temperature 20–25°C (room).
• ⏳ Device stabilization time of at least 15 minutes.

💡

If the error remains after calibration, check the device for physical damage.Cracks on the body, moisture or a fall from a height can cause the sensor to fail without the possibility of repair.

Alternative calibration methods

If the standard methods don’t work, try one of the alternative methods:

1. Calibration through firmware (for advanced users)

Some models (e.g. Mi Thermometer 2) allow you to edit firmware configuration files.

1. Download Mi Home Hack (available on GitHub).
2. Connect the thermometer to the PC via Bluetooth.
3. In the file config.json find a line "temp_offset": 0 and change the value (for example, to "temp_offset": -0.3).
4. Download the modified firmware back to the device.

2. Use of third-party applications

For fitness bracelets suitable:

• 📱 Notify & Fitness for Mi Band (Android) – allows you to manually adjust temperature readings.
• 📱 Tools & Mi Band – Temperature Adjustment».

3. Hardware calibration (for advanced users)

If you are an electronics expert, you can calibrate the sensor with a multimeter:

1. Find a resistor on the thermometer board NTC (thermistor).
2. Measure its resistance at a known temperature (e.g., in an ice glass).
3. Compare with the reference values from the datashit and solder an additional resistor for adjustment.

⚠️ Warning: Hardware calibration voids warranty and can cause the device to fail. Use this method only if all other options have been exhausted.

FAQ: Answers to Frequent Questions