The DS18B20 is a waterproof digital temperature sensor sealed inside a stainless steel probe. It speaks 1-Wire — one GPIO pin, one data wire, and you can chain multiple probes on the same line, each with its own unique address burned in at the factory. Choose your cable length above: 1m, 3m or 5m.
- Sealed stainless steel probe — IP67 waterproof
- 1-Wire protocol — one GPIO pin for any number of sensors
- -55°C to +125°C range, ±0.5°C accuracy (-10°C to 85°C)
- 9–12 bit configurable resolution
- Chain multiple probes on a single data line
- Works with Arduino, ESP32 and Raspberry Pi
- Choose 1m, 3m or 5m cable length
- 3.0–5.5V supply or parasite power mode
Specifications
What's in the box
A 4.7kΩ pull-up resistor is required and not included — most Arduino starter kits include one, or add our DS18B20 adapter module which has the pull-up already fitted.
Great for
Common questions
Which cable length should I choose?
Pick the run between your probe and controller: 1m for benchtop and small tanks, 3m for most fixed installs, 5m when the controller is across the room or outside. All three are the same sensor — only the cable length differs.
Do I really need a pull-up resistor?
Yes. A 4.7kΩ resistor between the data wire and VCC is required. Without it you'll get 85°C (the power-on default) or -127°C (a communication error) instead of real readings. Our DS18B20 adapter module has one already fitted.
Can I chain multiple probes on one wire?
Yes. All probes share the same three wires. Each sensor has a unique 64-bit address so you can read them individually. One pull-up resistor handles a short run of probes.
Can the probe be fully submerged?
Yes, it's IP67 rated. Try to keep the cable exit point above the waterline for permanent builds — the probe itself handles full submersion.
Will it work with a Raspberry Pi?
Yes. Enable 1-Wire in raspi-config (add dtoverlay=w1-gpio to /boot/config.txt) then read from /sys/bus/w1/devices/.
Good to know: Wire colours — Red is VCC (3.3–5V), Black is GND, Yellow is Data. A 4.7kΩ pull-up between Data and VCC is required but not included — grab our DS18B20 adapter module if you'd like it pre-fitted with a screw terminal.