How many BLE device for each ESPHome?

Hi everyone,
Since I’ve bought my first MiFlora sensor but is too far from my Home Assistant Hub I decided to try ESPHome for the first time. At the moment I’m really satisfied it!
Since I’m planning to buy a couple more of MiFlora sensors I was wondering how many Miflora sensor can I associate with a single ESP32?

Thank you in advance

I think there don’t is a “hard” limit but it all depends on the memory your esp32 has (maybe a version with psram could handle more than).

You could try to multiply your configuration (and editing each MAC to a different one) too see if compiling fails at some point or if the device starts to get instabilities. But maybe both does not occur if you don’t try with a real “load” (ble sensors) - but should be worth a try :wink:

Please share your findings if you come across some :stuck_out_tongue:

Thank you for your answer!
I’ll try to buy a couple of Xiaomi sensors and add them to the ESPHome yaml.
In theroy if the compiling doest’t fail the ESP-WROOM-32 should handle multiple sensors, right?
Since those ESP32 are quite cheap is not a big issue to use multiple of them but I’d like to save space and limit the number of wifi connected devices…

Anyway I’ll share my findings!

It could still fail while running. But when it already doesn’t “complain” while compiling it is already a sign of hope :stuck_out_tongue:

Indeed, best success should be anyway with a Ethernet connected esp32 because than the antenna can be 100% of the time care about BLE. If you use wifi it actually always “toggles” between wifi and ble because they share the same antenna


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I have one esp32 and 8 Xiaomi BT thermometers running perfectly. Esp32 has external classic wifi antenna on 5cm wire, BT signals are from -60 down to -95, but still running fine at such low level. Currently i have two versions: one is tasmota, other is esphome (using esp-idf framework), but only to compare two “technologies” for stability. At later stage i’ll probably stick with esphome only.

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If have running 9 MiFlora with 1 ESp32 withour issue mor than a year.
It has dust sensor and temperature on board. No problem.
Only thing is, that ota updates dont work.
Version is:
ESPHome version 2021.10.2 compiled on Oct 26 2021, 07:47:08

Best regards,

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The limit is fairly high, I am running a lot of BLE devices via different ESPs. In my case I have all my BLE devices set up on all my ESP32s, so I can track them. This means, my most “connected” ESP has the code for thirteen different BLE devices running without any problems. Six of these devices are somewhat the same like the MiFlora sensors (enhanced DIY version), a few thermometers from Aqara/Xiaomi and all the tracking stuff, with phone and BLE trackers.

I can safely say, in a normal setup, you will most likely not get near any limitiations. :slight_smile:


I am running one ESP32 for 15 BLE Devices (2 Mi flora and 13 Mi Temp/Humid sensors) and am expecting some Issues with them. In some reading intervals all entity values are null, i think the RAM gets overflow when too many device sending their values in the same moment.

What does the debug component tells you/us? :thinking:

for any reason the problem is gone at the moment… :o
will do this if it comes back.