> For the complete documentation index, see [llms.txt](https://docs.blynk.io/en/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.blynk.io/en/blynk-library-firmware-api/installation/install-esp8266-core-for-arduino-ide.md).

# Install ESP8266 core for Arduino IDE

1. Install latest [Arduino IDE](https://www.arduino.cc/en/Main/Software).
2. Download and install Blynk library\
   (follow instructions of the latest [release package](https://github.com/blynkkk/blynk-library/releases/latest)).

Then, open the Arduino IDE, then select in the menu: `File -> Preferences`\
(`Arduino -> Preferences` for Mac).

Click on **Additional Boards Manager URLs** button and add this link:

```
http://arduino.esp8266.com/stable/package_esp8266com_index.json
```

![](https://uploads.intercomcdn.com/i/o/20866093/60ae89223dd38335c61e0f68/file_preferences.png)

In the Arduino IDE open: `Tools -> Board -> Boards Manager` .\
Search for `esp8266` , and install it:

![](https://uploads.intercomcdn.com/i/o/20866111/4bfaa4bd6bb2547a890ccfd3/boards_manager.png)

### Troubleshooting <a href="#troubleshooting" id="troubleshooting"></a>

In case you see Error downloading <http://downloads.arduino.cc/packages/package_index.json> like this:

![](https://uploads.intercomcdn.com/i/o/20866154/50e8eefe4218e5a69fb62f03/error_download_mac.png)

You need to find folder `Arduino15` or `.Arduino15` and remove all files inside with package word in name.<br>


---

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