NodeMCU DHT11 HTTP Telemetry
An ESP8266 that posts live temperature readings to a hosted server on its own.
The problem
A sensor reading that never leaves the microcontroller isn't data yet. I wanted the board to push readings to a backend by itself, with no laptop in the loop, and have them stored where something else could use them.
What I built
The firmware connects to WiFi, reads the DHT11, and POSTs temperature and humidity to a hosted server that persists each reading. I kept a stripped-down POST sketch next to it, which turned out to be the fastest way to check whether an endpoint and the network were behaving before adding the sensor back into the picture.
- DHT11 temperature and humidity read on the ESP8266 and sent over WiFi
- Continuous HTTP POST to a hosted server that stores every reading
- Separate minimal sketch for testing endpoints and connectivity
- HTTP and HTTPS POST examples for calling remote APIs from the device
How it turned out
Built over three days in September 2025. Small, but it closes the loop from sensor to database, and I've reused it as a starting point since.