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ESPHome

DHT11 and DHT22 with ESPHome: Wiring and Configuration

26/08/2026
DHT11 and DHT22 sensors with ESPHome

Updated August 26, 2026 · Comparison, pull-up resistor, safe GPIO selection, and ESPHome configuration reviewed.

The DHT11 and DHT22 are inexpensive digital temperature and humidity sensors. They are useful for learning ESPHome or making a simple environmental measurement, but their capabilities differ and both require correct wiring. This guide uses a GPIO that does not control boot mode and an external pull-up resistor when the module does not already include one.

DHT11 vs DHT22

CharacteristicDHT11DHT22 / AM2302
Typical temperature range0 to 50 °C-40 to 80 °C
Typical temperature accuracy±2 °C±0.5 °C
Typical humidity range20 to 80% RH0 to 100% RH
Typical humidity accuracy±5% RH±2 to 5% RH depending on range and version
Maximum reading rateAbout once per secondAbout once every two seconds
Best useBasic experiments and minimum costWider range and better accuracy

Specifications vary between manufacturers and clones. A DHT22 is generally the better of these two for room monitoring. For new projects that need stable measurements, I²C sensors such as SHT3x or BME280 usually provide better repeatability. The HTU21D ESPHome guide covers another digital option.

Bare sensor or breakout module

A bare four-pin sensor normally needs a pull-up resistor between DATA and 3.3 V. ESPHome recommends about 4.7 kΩ, with 1–10 kΩ commonly working. Many three-pin breakout modules already include this resistor, so inspect the board before adding another.

  • VCC: 3.3 V in this build.
  • DATA: GPIO4.
  • NC: no connection on the four-pin package.
  • GND: common ground.
  • Pull-up: 4.7 kΩ between DATA and 3.3 V if not included.

Always view the sensor from the orientation shown in its own datasheet. Breakout modules can rearrange the connector. Reversing VCC and GND can permanently damage the sensor.

Why the old GPIO0 example should be replaced

GPIO0 selects the ESP8266 boot mode. If a sensor, resistor, or wiring fault holds it low during power-up, the microcontroller enters programming mode instead of starting ESPHome. GPIO2 and GPIO15 are also boot-strapping pins.

Use GPIO4, labeled D2, on a Wemos D1 mini or NodeMCU. GPIO5 (D1) is another common choice. On an ESP32, GPIO27 or another suitable free pin can be used after checking the exact board. Do not confuse D2 with GPIO2: D2 is GPIO4 on a Wemos D1 mini.

ESPHome configuration for DHT22

sensor:
  - platform: dht
    pin: GPIO4
    model: DHT22
    temperature:
      name: "Room temperature"
      accuracy_decimals: 1
    humidity:
      name: "Room humidity"
      accuracy_decimals: 1
    update_interval: 30s

Setting model: DHT22 avoids relying on automatic detection. An interval of 30 or 60 seconds is appropriate for a room and reduces failed reads. Polling faster does not make the sensor respond more accurately.

ESPHome configuration for DHT11

sensor:
  - platform: dht
    pin: GPIO4
    model: DHT11
    temperature:
      name: "DHT11 temperature"
    humidity:
      name: "DHT11 humidity"
    update_interval: 30s

AM2302 normally belongs to the DHT22 family. ESPHome also lists specific models for variants that do not exactly match the expected protocol. Read the logs before changing model options at random.

Placement and enclosure

  • Place it in moving air, away from the board’s regulator.
  • Avoid direct sun, heaters, window drafts, and condensation.
  • Do not seal it inside an unventilated enclosure.
  • Use short wiring during initial testing.
  • For several-meter runs, improve wiring and decoupling or choose a more suitable bus.

Heat from an ESP8266 or power supply in the same box can raise the reported temperature. Physically separate the DHT and provide lower and upper vents so air can circulate.

Erratic readings and NaN values

ProblemRecommended check
No readingsPinout, common ground, model, and actual GPIO number
Checksum errors4.7 kΩ pull-up, shorter cable, and stable power
ESP8266 will not bootMove from GPIO0/GPIO2/GPIO15 to GPIO4 or GPIO5
Temperature too highMove the sensor away from the board and ventilate the enclosure
Humidity fixed or implausibleCompare against another instrument and replace a contaminated sensor

Calibration in ESPHome

Do not correct a reading from a single comparison. Place both instruments together, allow them to stabilize, and compare several conditions. If the error is approximately constant, apply an offset:

temperature:
  name: "Room temperature"
  filters:
    - offset: -0.6

An offset cannot repair hysteresis, condensation, or a faulty sensor. Use a calibrated instrument for important decisions and document any correction.

Verified sources