HomeHome AutomationHow to flash Tasmota on Sonoff DualR3

How to flash Tasmota on Sonoff DualR3

Making Sonoff DualR3 mine!

This article is greatly delayed, as I accidentally killed my Sonoff DualR3 during my review. If you want to know what happened and laugh at my mistakes, feel free to check the article out. ITEAD was kind enough to send me another one, knowing that I will disregard their eWeLink app and jump straight into flashing. Unfortunately, the method isn’t as simple as with other ESP8266 based devices as Sonoff DualR3 is ESP32 based and all-new ITEAD devices will be ESP32 based as well.

Tasmota on Sonoff DualR3

I’m sad to report that Sonoff DualR3 doesn’t even come with Sonoff DIY mode, which would make thigs easier. The DIY mode is good enough for most of my uses, but if you want to take Sonoff DualR3 a step further, you have to flash the device in a more traditional way. I will have to reach out for my good old soldering iron (I recently upgraded from TS80 (review) to TS80P (review pending) and FTD1232.

As brilliant Tasmotizer for ESP8622 devices is out of the picture, I had to look elsewhere to get the tools for the job. Thankfully, some work already been completed in this GitHub discussion, so I will base my tutorial on their findings.

List of downloads:

To flash Tasmota on Sonoff DualR3, you will need to connect the usual pins to the device. Thankfully, dev pads are properly exposed, and the button is linked to GPIO00. Follow the table below to connect your FTD1232 (or similar) to Sonoff DualR3:

Sonoff DualR3FTD programmer

Do not flash the ESP32 with Sonoff DualR3 connected to mains. FTD1232 is enough to power the pins and flash Tasmota on Sonoff DualR3. To enter flash mode, hold down the button on Sonoff DualR3 while power cycling the device.

ESP flasher & custom Tasmota firmware

Software is self-explanatory, open the software, select the tasmota32.bin from your drive, select the port to which the device is connected and hit flash. You should be done in a couple of minutes. If all went well, you should see “tasmota-XXXXX” SSID after reboot. Connect to that SSID and navigate to

Enter credentials (and hostname) and reboot your device. You can use the Fing app to find the device on the networks again or use the hostname. Navigate to Configure->Configure Other and use this template to configure Tasmota on Sonoff DualR3. After reboot, you should see a familiar menu with 2 channels to toggle and energy use information.

{"NAME":"Sonoff Dual R3","GPIO":[32,0,0,0,0,0,0,0,0,576,225,0,0,0,0,0,0,0,0,0,0,7296,7328,224,0,0,0,0,160,161,0,0,0,0,0,0],"FLAG":0,"BASE":1}

Bear in mind, that this firmware is a custom build. I have compiled this from source, and until properly integrated with the tasmota32 dev branch. Upgrading the firmware with binaries from the official channel may break the functionality of Tasmota on Sonoff DualR3.

Going further

Despite being in beta, Tasmota for ESP32 works pretty well, the interface is responsive and updates switch state changes reasonably quickly (about 1 sec). Power metering accuracy is on par with what I got with the eWeLink edition, the only thing that is not present is the data logging. This is something you will have to do yourself. My recommendation would be to use Grafana and InfluxDB – and as it happen, I have a handy tutorial for you to get you started.

Now, you will be able to take advantage of the REST API and MQTT. If you want to learn how to integrate these with NodeRED – I have tutorials available already. If you need Alexa integration – here is an article for you, and for Google Assistant – take advantage of NORA. Should you wish to recreate fancy features like inching or interlocking – I also covered this for you.

Buy Sonoff Dual R3

Buy it using these links to support NotEnoughTech.

Final Thoughts

Although Sonoff DualR3 comes without DIY support, flashing Tasmota on Sonoff DualR3 isn’t a total pain in the neck, and has to be done just once. I hope that ITEAD will rethink the approach to new devices and add Sonoff DIY by default. My source tells me that all future Sonoff devices will be ESP32 based, so it would be nice to see Tasmota and Tasmotizer evolving more in that direction. If you have any comments, feel free to let me know in this Reddit thread.


Nothing says "Thank you" better than keeping my coffee jar topped up!


Support me on Patreon and get an early access to tutorial files and videos.


Bitcoin (BTC)

Use this QR to keep me caffeinated with BTC: 1FwFqqh71mUTENcRe9q4s9AWFgoc8BA9ZU

Smart Ideas with

Automate your space in with these ecosystems and integrate it with other automation services


Learn NodeRED

NodeRED for beginners: 1. Why do you need a NodeRED server?

To server or not to server? That's a very silly question!

Best Automation Projects

Tuya SDK for beginners: Intro to Tuya Cloud API

Working with Tuya Cloud API. A guide to Cloud automation for beginners, get started with REST!

NEST your old thermostat under $5

Nest-ing up your older thermostat under $5

DIY Smart Washing Machine – for about 15 bucks!

Learn how to add washing machine notifications to your Google Home on the cheap

Nora – Google Assistant in NodeRED

Integrate Google Assistant with NodeRED thanks to Nora - NodeRED home automation

Things they don’t tell you about IKEA Trådfri

There are things you should know about IKEA Tradfri before you make your purchase

Smart Home

SwitchBot Lock: Smart security in seconds

Smart lock that takes 15 min to install and 2 years to enjoy on a single charge: SwitchBot Lock

“Secret” Zigbee2MQTT Dashboard

Zigbee2MQTT Dashboard
I can't believe no one told me about this sooner. After 2 years, I'm making sure you are not left in the same as me, cave - use Zigbee2MQTT Dashboard.

Smart Socket – IFREEQ [Tuya Expo edition]

Thanks to Tuya Expo, you can browse 100s of products that won't break your home automation budget - let's start with IFREEQ Smart Plug

Never mind Evvr Smart Switch, look at that panel!

Evvr Smart Switch brings 2 part module to enable no-neutral ZigBee and Z-Wave connections to your wall switches turning them smart without compromise!

Aqara TRV will support Matter!

Aqara just released Aqara TRV - their ZigBee 3.0 thermostatic radiator valve to control your heating - with... Matter support