If you like developing for theESP32, then you've probably already set upESPHome,Arduino IDE, or PlatformIO for building and testing your own projects. However, what if I told you that you could develop, build, and flash to your ESP32without needing to install any software on your computer? That's where FlashESP comes in, as it essentially puts the Arduino IDE in your browser, making it easy for you to build, flash, and monitor, all from the one window.

FlashESP is entirely free, and I met its developer at this year's Maker Faire Shenzhen. While the tool is already capable of quite a lot currently, the developer intends to build PlatformIO and ESP-IDF support into it as well, and already has functioning pipelines for PlatformIO when it comes to automatic building and deployment. It's not available yet, but should be in the near future. Users who sign up can manage up to ten projects for free, and as I've played around with FlashESP over the past week and a half, I've been very impressed.

Note that, technically speaking, some usersmay need to install the CH340 or CP2102 driver, depending on the UART to USB adapter built into their ESP32. Windows will usually come with this driver preinstalled, but the developer of FlashESP tells me that the site will also prompt users who don't have it to install it.

Creating a FlashESP project

Defining project parameters is easy

Setting up FlashESP is completely free, and right now, users get space for ten projects that they can host at a time. Projects can be publicised and made discoverable on the site, or you can store them privately. As well, you can upload your own files or write them using an editor in your browser, and you can configure the entirety of your board settings from a series of dropdowns tailored to the specific ESP32 that you have. I actually prefer this layout over the typical Arduino IDE.

Once you've selected your options, you can create a new file called "libraries_lock.json" to define any dependencies and their versions that you may need. It looks like the following:

{
 "libraries": [
 {
 "name": "ArduinoJson",
 "version": "6.21.3"
 },
 {
 "name": "PubSubClient",
 "version": "2.8.0"
 },
 {
 "name": "DHT sensor library",
 "version": "1.4.4"
 }
 ]
}

Once you've got those prepared, you're ready to start building and flashing your device image. The build happens server-side, and flashing uses the WebSerial API in a Chromium-based browser to download the firmware file, then flash and monitor your ESP32. At the end of the build process, you'll get a compiled firmware file, manifest file, and the complete log of the build in case something failed. If it was successful, you can then clickFlash, and have it automically go to your ESP32.

All Arduino IDE ESP32 boards are supported, and the same goes for libraries. The Arduino version supported at the time of writing is 3.3.2, based on ESP-IDF v5.5.1, and is selected when creating a project. As well, when creating a project, you can make it private, unlisted, or public, and you can add tags and a description. If you want to look at other people's projects, you can favorite them on the site, though there aren't many that are public right now. FlashESP's developer also says that GitHub support for synchronization and importing will come in the future.

This project is primarily aimed at education contexts, and there will be "course-ready onboarding packs" in the near future, with a complete education platform rollout over the coming months. By building what essentially amounts to the Arduino IDE in a user's browser, it removes many of the barriers that would typically prevent them from getting started in the first place. For educators, that ease of entry is a massive plus, and may make it easier to get children interested in microcontroller development, for example.

Flashing is just as easy, too

If you're familiar with ESPHome or tools such as ESPressoFlash, then you likely know how web-based ESP32 flashing works. You pick your device from the device picker, and your browser then handles the serial connection between your PC and the ESP32. You can flash firmware updates and files this way, and ESPFlash is no different. By clicking flash after building your project, you choose your device, click connect, and you can then view the serial monitor after it finishes flashing the firmware file in order to keep an eye on real-time device logs.

If you want to check out what shared projects look like,you can see my project that I built. It hosts a basic web server on an ESP32-S3, and you can check out the source code, compiled firmware, manifest, and when it was last updated. It's a pretty neat way to share a project with someone, and looks quite nice given that it's just a basic web-based editor. While I tend to work in PlatformIO rather than the Arduino IDE when writing for the ESP32, the Arduino IDE can still be useful, especially for simpler projects. Plus, with PlatformIO support coming soon, it'll make developing those projects a whole lot easier no matter where I am.

For more die-hard developers, this tool willnot replace your workflow, but it's also not trying to. It's designed to lower the barrier to entry for people to get started, and for that, it does an amazing job. You can even quickly flash and try out a demo on the FlashESP site if you have a standard ESP32 or ESP8266. Definitely give it a try!