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Reading Temperature and Humidity from a DHT11 on a Raspberry Pi 4B

Wire a DHT11 temperature/humidity sensor to a Raspberry Pi 4B GPIO pin and read live values in Python — wiring, starter code, and how to confirm it's really working.

Try this directly in the free Raspberry Pi 4B simulator — no hardware or signup required. New to the GPIO header? Start with the interactive pinout guide.

What you’ll need

  • Raspberry Pi 4B
  • DHT11 Temp/Humidity Sensor

Step by step

  1. Drag Raspberry Pi 4B onto the Canvas.
  2. Drag the DHT11 onto the Canvas.
  3. Hover over its pins to confirm the actual labels — most likely VCC, DATA, GND.
  4. Wire it up: VCC → Pi's 5V (check the component's hover tooltip or settings panel to confirm the correct voltage, since DHT11 breakouts vary by brand). GND → Pi's GND. DATA → any GPIO pin (e.g. pin 37).
  5. Go to the Code tab and write a test script:
import adafruit_dht
import board
import asyncio
 
dht = adafruit_dht.DHT11(board.D37)   # adjust pin to match your wiring
 
while True:
    try:
        temperature = dht.temperature
        humidity = dht.humidity
        print(f"Temp: {temperature}C  Humidity: {humidity}%")
    except RuntimeError as e:
        print(f"Reading error: {e}")
    await asyncio.sleep(2)
  1. Click Start.

What “working correctly” looks like

  • A temperature and humidity value print repeatedly, staying reasonably stable — small natural fluctuation is fine, wild jumps on every read are not.
  • If this component has a settings panel, check it when selected — you may be able to set a custom simulated value directly, worth testing by setting an extreme value (e.g. 40°C) and confirming the script reads back exactly that.

If something’s wrong

  • Import error, or nothing happens at all → check this component's own example/starter code in the app for the actual expected approach, rather than trusting the script above as final.