ESP-NOW in simple terms
ESP-NOW is a communication protocol developed by Espressif, the company that makes ESP32 chips. With traditional Wi-Fi, every device has to connect to a router. With ESP-NOW, one device talks directly to another, a bit like two walkie-talkies that need no network to communicate.
In short: it is the most direct way to get ESP32 devices talking to each other. Want to connect many of them? Read how an ESP-NOW network of boards works.
Why ESP-NOW is useful
No router
Devices can communicate even where there is no Wi-Fi network.
Fast response
There is no connection to wait for: messages go out straight away.
No internet
It works on its own, without relying on external services.
Protected communication
Messages can be encrypted.
How ESP-NOW works
Each device has its own address: the sender transmits the message by radio directly to the device that needs to receive it.
They recognise each other
Devices are programmed to know which others they can communicate with.
They exchange messages
A sensor, for example, sends a short piece of information to another device.
They react
The receiver carries out the planned action, such as switching on an output or updating a display.
Is ESP-NOW reliable?
Yes, if the system is well designed. As with any radio technology, there are points to consider:
- Range: this depends on the surroundings, such as walls and obstacles, and should be tested on site
- Short messages: it suits commands and small amounts of data, not video or large files
- Lost messages: the firmware can check that messages arrive and resend them if needed
- Privacy: encryption can stop others from reading the messages
ESP-NOW for your ESP32 product
At StepLab we develop firmware with ESP-NOW communication for ESP32-based devices. We have already used it in real projects, such as the smart battery charger and the Solaria system.
- We assess whether ESP-NOW is the right choice for your application
- We develop the firmware and define which messages the devices exchange
- We test operation on the real hardware
What is needed? ESP32-based devices close enough to communicate by radio. If you need to control them from far away, you also need an internet connection, which we can integrate. See all our services on the ESP32 programmers page.
ESP-NOW FAQ
Does ESP-NOW need the internet?
No. Devices communicate directly with each other, with no router and no internet.
Can ESP-NOW work alongside Wi-Fi?
Yes, with firmware designed for it: the same device can use ESP-NOW and also join a Wi-Fi network.
How far does it reach?
It depends on the surroundings and the board's antenna. Walls and obstacles reduce the range, so it is best to test it where it will be used.
Does it work with non-ESP32 devices?
ESP-NOW is an Espressif technology, used between devices based on its chips. To connect other equipment, an ESP32 can act as a bridge.
Contact us
Want your devices to communicate with ESP-NOW? Write to us or give us a call.