Give your next Arduino project the ability to sense the world around it with the inexpensive DHT11 or DHT22 Digital Temperature & Humidity Sensor from AOSONG.
These sensors are pre-calibrated and don’t require extra components so you can start measuring relative humidity and temperature right away.
One of the greatest features they provide is that both temperature & humidity are measured to the nearest tenth; that is, to one decimal place. The only downside of this sensor is you can get new data from it once every second or two. But, considering its performance and price, you can’t complain.