How to measure the pressure with Xiaomi smart watches: instructions with nuances

Xiaomi smart watches have long ceased to be just an accessory for tracking steps.Modern models - from the budget Mi Band 7 Pro to the flagship Xiaomi Watch S4 — They're equipped with sensors that can measure blood pressure (BP) without a traditional blood pressure monitor. But how does it work in practice? Can you trust the clock screen, and why the results sometimes diverge from the mechanical device?

In this article, we will analyze the step-by-step pressure measurement algorithm on Xiaomi watches, find out which models support the function, and learn how to interpret the data. Particular attention will be paid to typical errors that cause the device to show inaccurate values, such as improper fitting of a strap or movement of the hand during measurement, and you will learn how to calibrate the watch to your individual parameters to improve accuracy.

Importantly, the pressure measurement function in a smartwatch is not a medical device, but a support tool, and it's not a substitute for a doctor's consultation, but it can help you track your daily life, and if you have hypertension or other cardiovascular conditions, use this watch as an addition to traditional control methods.

What Xiaomi watches can measure pressure?

Not all Xiaomi smartwatches are equipped with a pressure sensor, a feature available in the following series (2026):

• 📌 Mi Band 7 Pro and newer (including Mi Band 8 Pro) – with support PPG-BP-tester.
• 📌 Xiaomi Watch 2 and Watch 2 Pro – the first watch of the brand with full monitoring of pressure.
• 📌 Xiaomi Watch S1/S2/S3 — flagship models with improved sensors and algorithms.
• 📌 Xiaomi Watch Color 3 and Redmi Watch 3 Active – budget options with basic function.

Note: Mi Band 6 and older models (e.g. Mi Band 5) do not provide pressure measurements, only pulse and saturation. S1 It is not available in the Chinese version).

To check if your model supports pressure measurement:

1. Open the Mi Fitness app (or Zepp Life for new models).
2. Go to the Device section → Health functions.
3. Check for blood pressure or blood pressure.

Preparation for Measurement: 5 Rules for Accurate Data

Even the most advanced Xiaomi watches will show incorrect results if you do not follow the measurement conditions.

• ☕ Eliminate caffeine and nicotine, which temporarily increase blood pressure. Do not smoke or drink coffee/energy in at least 30 minutes.
• 🏃 Rest after exercise or fast walking, wait 20–30 minutes.
• 🚽 Empty the bladder - a full bladder can distort the readings by 5-10 mm Hg.
• 🧘 Relax – sit still for 5 minutes before measuring, do not talk.
• 📵 Remove tight clothing – the sleeve should not crush the hand above the hours.

Pose during measurement is also important.

• Sitting on a chair with a backrest.
• The hand with the clock lies on the table at heart level (you can put under the elbow roller).
• The legs are on the floor, not crossed.

⚠️ Attention: If you measure pressure standing or lying down, it can be 5 to 15 mm Hg from the actual pressure, and lying down is usually slightly lower than sitting down.

Step-by-step: how to measure the pressure on the watch Xiaomi

The algorithm for starting the measurement depends on the model of the watch, but the overall scheme is the same. S3 (For other models, the steps are similar, only the names of menu items may differ).

1. Put the watch on correctly: the strap should fit tightly to the wrist (but not pressed), and the sensor on the back should touch the skin, a gap of 1-2 mm will distort the results.
2. Activate the function: On the clock: go to the Health menu → Blood pressure (or Health) → In the app: Open Mi Fitness → The device → Pressure measurement and press Start.

Follow the instructions on the screen

sit down

hold off

Wait for the result

systolic

diastolic

Save the data.

Mi Fitness

Zepp Life

On the Mi Band. 7 Pro/8 The path of the function may be different:

Main screen → Scroll down → Heart Badge → Blood pressure

⚠️ Warning: If the watch shows an error Can not be measured, check: Density of the strap (sensor must touch the skin), No movement of the hand during the measurement, ambient temperature (at the time of the measurement) <10°C or >40°C sensor may not work).

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If the clock is constantly showing an error, try restarting the device: press the power button for 10 seconds. After restarting, repeat the measurement.

Calibration of the clock: why it is important and how to do it

Smart watches Xiaomi measure pressure indirectly – by pulse wave (PPG-The sensors and machine learning algorithms, so to be more accurate, you have to calibrate the device to your individual settings. ±15-20 mm Hg - this is critical for people with hypertension.

Calibration will require a mechanical or electronic tonometer (preferably with a cuff on the shoulder).

1. Measure the pressure with a blood pressure monitor 2-3 times at intervals of 1 minute. Write down the average value.
2. Immediately after that, measure the pressure with a Xiaomi watch (in the same body position).
3. If the difference is greater than 10 mm Hg, calibrate in the app: Open Mi Fitness → Profile → The device → Pressure settings. Select Calibration and enter the blood pressure meter. Confirm the retention.

Calibration is recommended to be repeated every 1-2 months and after:

• 🔋 Updates to the firmware of the watch.
• 🏋️ Significant changes in physical activity (for example, after starting exercise).
• 💊 Prescribing new medications that affect pressure.

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Calibration reduces the error by 30-50%, without which the Xiaomi watch only gives approximate data, unsuitable for medical conclusions.

Transcription of results: what do the numbers on the screen mean

On the screen of the clock after the measurement you will see two numbers - for example, 120/80. What do they mean?

• 📊 The first number (systolic pressure) is the pressure in the arteries at the time of heart contraction. Normal: 90-120 mm Hg..
• 📊 Second number (diastolic pressure) is the pressure in the arteries between heartbeats. Normal: 60-80 mm Hg..
• ❤️ Pulse (HR) — Normal resting: 60 to 80 beats/min.

In the Mi Fitness or Zepp Life app, the results are supplemented by graphs and classification:

• 🟢 Normal – systolic 90-120, diastolic 60-80.
• 🟡 Elevated - systolic 120-139, diastolic 80-89 (prehypertension).
• 🔴 High-systolic ≥140, diastolic ≥90 (hypertension).
• 🔵 Low-grade-systolic. <90, diastolic <60 (hypotension).

Important: pressure standards are individual and depend on age, gender and fitness, for example, athletes at rest often have pressure. 100/60, In older people, the norm may be 130/85. Do not panic at single deviations - pay attention to the dynamics (measure the pressure at one time of the day for several days in a row).

Common Mistakes and How to Avoid Them

Users often experience inaccurate readings or errors in their blood pressure measurements, and here are the most common causes and solutions:

A few more nuances:

• 🌡️ Ambient temperature below 10°C or higher than 40°C can block the sensor. Measure the pressure in room conditions.
• 🔋 Low battery power (less than 20%) sometimes causes failures. Charge the clock before measuring.
• 🧴 Creams and wrist tattoos interfere with the sensor.Wash your skin with alcohol before measuring.

⚠️ Note: If you wear a watch on your right hand and you usually measure pressure on your left hand (or vice versa), the readings may vary by 5-10 mm Hg due to anatomical features.

Medical tonometer comparison: how accurate is Xiaomi watch?

Clinical studies show that smartwatches (including Xiaomi) have a margin of error of 10–20 mm Hg compared to mercury or automatic tonometers.

• 🩺 Medical tonometer measures pressure directly - by the strength of air resistance in the cuff.
• ⌚ Smart watches measure indirectly – by pulse wave and algorithms trained on big data.

In 2023, the journal Hypertension published a study comparing the accuracy of 10 popular smartwatches. S2:

• 🎯 Systolic pressure: error ±12 mmHg in 70% of cases.
• 🎯 Diastolic pressure: error ±10 mmHg in 65% of cases.

This means that Xiaomi watches are suitable for:

• 📈 Tracking trends (such as how blood pressure changes after sleep, exercise, or stress).
• 🚨 Operational control (if you feel unwell).

But not suitable for:

• 🏥 Diagnosis of hypertension (need a medical tonometer).
• 💊 Correction of drugs (doses of drugs are prescribed only by a doctor).

If you want high accuracy, use the Xiaomi watch as an additional tool, not a replacement for the tonometer. 140/90, Measure the pressure with a mechanical device - it may be a false positive.

FAQ: Answers to Frequent Questions