7 of the 10 features in our table differ between the DS18B20 and the DHT22.
±0.5 °C · temperature only · 1-Wire · 3 to 5.5 V
A 1-Wire temperature sensor, ±0.5 °C from −10 to 85 °C, often sold in sealed probes for water, soil and outdoors.
Watch out: Temperature only, and up to 750 ms per 12-bit reading. The data line needs a pull-up resistor.
±0.5 °C · ±2 %RH · Single wire (own protocol) · 3.3 to 6 V
A step up from the DHT11: ±0.5 °C, ±2 %RH typical and down to −40 °C, still on one data wire.
Watch out: The humidity error can reach ±5 %RH, one reading every 2 s at most, and its own protocol needs precise timing. About 50 µA between readings.
| Feature | DS18B20 | DHT22 |
|---|---|---|
| Measures | temperature | temperature · humidity |
| Humidity accuracy | No humidity | ±2 %RH |
| Temperature range | −55 to 125 °C | −40 to 80 °C |
| Interface | 1-Wire | Single wire (own protocol) |
| Supply | 3 to 5.5 V | 3.3 to 6 V |
| Current between readings | 0.75 µA | 50 µA |
| ESPHome | dallas_temp | dht |
Same on both: temperature accuracy · status.
Open the sensor comparison →Tick what your project needs and see which sensor fits best.
The DS18B20 offers a wider temperature range, less current between readings, and sealed probes. The DHT22 offers humidity as well as temperature.
Typical datasheet figures for temperature: ±0.5 °C for the DS18B20 and ±0.5 °C for the DHT22. Only the DHT22 measures humidity (±2 %RH). Placement matters as much as accuracy: keep either away from the board’s warm parts.
Not as a drop-in: the DS18B20 uses 1-Wire and the DHT22 a proprietary single-wire protocol, so the wiring and the code change.
DHT22 vs BME280 DHT11 vs DHT22 AHT20 vs DHT22 DHT22 vs SHT31
Figures from the makers’ datasheets and product pages and the ESPHome documentation, checked in November 2026.