Heltec LoRa 32 Range Test – Real Off-Grid ESP32 LoRa Communication

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Last Updated on November 28, 2025 by Engr. Shahzada Fahad

Table of Contents

Description:

Today, I am finally putting the Heltec LoRa 32 boards to the ultimate range test; and trust me, the results are going to blow your mind.

You will finally see how to use the Heltec LoRa 32 modules the right way for real-world communication.

For this test, I have built a complete off-grid text messaging system; where we will send messages from one smartphone to another, entirely over LoRa, with no internet or mobile network involved.

This will show exactly how far we can send and receive messages effectively, even in remote areas.

And here’s the best part; the smartphone apps I am using for this test are custom-built by me.

So stay tuned, because in this article, we are going deep into real off-grid LoRa communication like never before.

While the manufacturer specifies that the Heltec LoRa 32 can achieve communication distances of up to 21 kilometers, it’s important to understand that this figure is based on ideal laboratory or open-field conditions.

In real-world scenarios, the actual communication range can vary significantly depending on several factors.

Antenna placement and alignment play a crucial role — a well-positioned antenna with a clear line of sight can greatly enhance signal strength, whereas an antenna placed indoors or near metallic structures can reduce performance. Terrain and environmental conditions also matter; open rural areas provide much longer range compared to urban environments filled with buildings, trees, or electrical interference.

Additionally, transmit power, receiver sensitivity, and data rate (spreading factor) directly impact how far reliable communication can be maintained. Lower data rates allow longer range but slower transmission speeds, while higher data rates shorten the effective distance. Even atmospheric conditions such as humidity and temperature can influence signal propagation over long distances.

Therefore, while the 21 km specification highlights the potential of the hardware, achieving that range in practice depends on careful hardware setup, environmental conditions, and LoRa parameter tuning.

However, I didn’t perform the range test in my previous video and article “Heltec LoRa 32 Getting Started Article” ; and there were a few reasons for that.

First, I wanted to keep things simple and beginner-friendly.

My main focus was on helping you get started; installing the board, setting up the libraries, and performing basic one-way and two-way communication.

It was all about understanding the basics before diving deeper.

Second, I didn’t receive the batteries with my shipment.

The courier service didn’t allow them due to shipping restrictions.

So, I couldn’t go completely wireless; I had to power up the modules using my laptop and a 5V adapter.

And as you know, for a proper range test, you definitely need batteries.

But now… things are different.

Amazon Links:

Heltec LoRa 32

Other Tools and Components:

ESP32 WiFi + Bluetooth Module (Recommended)

Arduino Nano USB C type (Recommended)

*Please Note: These are affiliate links. I may make a commission if you buy the components through these links. I would appreciate your support in this way!

Batteries Connection:

As you can see, I have finally powered up one of the modules using a battery.

So, how did I do it? Let me show you.

First, I bought these 1800mAh batteries from a local mobile shop. You can, of course, use batteries with higher or lower capacity depending on your requirements.

Next, using a digital multimeter, I identified the positive and ground terminals of the battery.

After that, I soldered the red and black wires, which already had a connector attached.

And thanks to Meshnology for providing this small battery connector cable; it made the setup much easier.

As you can see, after connecting the battery, our second module has also powered on.

Right now, both modules are running the two-way communication code. So, both the modules are ready for testing.

OFF-Grid Text Messaging using Heltec LoRa 32 Code:

First of all, you need to upload the code to both Heltec LoRa 32 boards.

You can download the code from my Patreon page.

Smartphone applications for Heltec LoRa 32:

I developed this application in Android Studio.

To send off-grid messages via LoRa, you will need to install this app on the mobile device you plan to use.

The source code for the app, along with the controller code, is available on my Patreon shop; all at a very reasonable price.

Practical Demonstration:

This mobile is paired with this LoRa module via Bluetooth, and the BLE status shows “connected”, which means it’s properly linked to the mobile application.

The second module is paired with another mobile device, and as you can see, its BLE status currently shows “waiting”… which means the mobile app is not yet connected.

So, let’s go ahead and connect it.

Now, the status has changed to “connected”.

At this point, I can send and receive text messages via LoRa using smartphones; completely off-grid and fully functional.

If your phone is in your pocket or on charging, you can still check the last sent and last received messages directly on the module’s display.

And not just that; you can also send commands to turn your loads ON and OFF.

For this demonstration, I am sending 1 and 0, but you can set any custom commands you want.

Our system is now completely ready for the range test… so let’s go ahead and find out just how far this tiny setup can really go.

Trust me, what you ARE about to see might surprise you.

Heltec LoRa 32 Range Test 1:

During Test 1, I was inside my lab, and my brother was standing at the far end of the house; roughly 60 meters away.

There’s just one room in between us, nothing too complicated… but still enough distance for a good first check.

And as you can see, I am receiving his messages without any issues.

So yeah; our first test is a solid success.

Typing and sending messages again and again takes a lot of time…

So for all the upcoming range tests, I am making one side fully automatic.

I uploaded the transmitter code from the one-way communication example “from my previous article”, and now you can see my module and the mobile app are receiving a continuous stream of random numbers.

And here’s the key point:

The moment the transmitter goes out of range, those numbers will stop updating inside the app.

Everything is ready now…

So let’s move straight into Range Test 2.

Heltec LoRa 32 Range Test 2:

For Range Test 2, I will stay inside the lab again…

But this time, my brother is taking the transmitter out on a bike, moving farther and farther away from the house.

This test is much tougher than the first one; because now we are dealing with a mix of indoor and outdoor communication, and between us, there are dozens of houses, hundreds of walls, and a completely congested neighbourhood in every direction.

So the real question is:

How far can LoRa push through this kind of dense environment?

I am staying on a call with my brother so he can update me on his exact location as he moves.

Let’s see what kind of range we get in this real-world jungle of obstacles.

A few moments later…

The incoming values have finally stopped.

No more updates — the link just dropped.

This is the maximum distance we could achieve with one module indoors, the other outdoors, and a huge number of obstacles in between; houses, walls, narrow streets, everything.

Considering how challenging this environment is, the results are actually pretty impressive.

Heltec LoRa 32 Range Test 3:

For Test 3, I have placed the module on the rooftop…

And as you can see, the data has started coming in again.

For me there is no need to stand on the Roof; so I am heading downstairs to my lab.

And this is the moment where I truly start appreciating how powerful this app really is.

Bluetooth keeps my phone connected to the module at short range; so I can walk around freely, check messages, send commands, and monitor everything…all without touching the hardware.

Short-range communication with Bluetooth… and long-range communication with LoRa…

What a combination. This setup honestly feels incredible.

Right now, I am standing here in the lab, the module is all the way on the rooftop… and my brother has gone even farther from his previous location — yet I am still receiving data perfectly.

Let’s fast-forward…

And there it is; the updates have finally stopped.

No more incoming numbers.

This is the maximum distance we are getting with both modules outdoors;

And let me tell you, there are still so many houses and obstacles in between.

The modules are not even in line of sight, yet the communication is holding up surprisingly well.

Heltec LoRa 32 Range Test 4:

For Test 4, this module is staying right here in the same spot…

But this time, my brother is heading all the way to the top of that mountain.

From my house to that mountain, the distance is roughly 1 kilometer.

So if both LoRa modules can communicate over this distance, then in real-world scenarios, I will practically be able to connect with any LoRa node in my entire village.

And once a module is placed on the mountaintop, we can even use it as a LoRa router; Pretty exciting stuff.

Anyways; I will be back; once my brother reaches the top of the mountain.

My brother has finally reached the top of the mountain…

And I hope you can spot him from here; he’s the one wearing the white dress.

Anyways, as you can see, I am receiving the numbers perfectly; no drops, no issues at all.

So the 1-kilometer range test is also completely successful.

Heltec LoRa 32 Range Test 5:

For LoRa Range Test 5, my brother is still standing on top of the mountain; and this time, I am heading back to my lab to see if I can still receive the data.

Honestly, I don’t think the signal will make it this far; but I want to test every possible scenario,

So we are doing this one as well.

Oh my God… I can’t believe this!

I am actually receiving data inside the room.

In my previous tests with other LoRa modules, they completely failed at this stage; so honestly, even right now, I am shocked. I still can’t wrap my head around it.

And let me tell you… when I placed the module down on the table, the signal completely dropped; no data at all.

So I lifted it and placed it a little higher inside the room; and ever since, it’s been working perfectly.

Sometimes, just changing the module’s height makes a huge difference in LoRa performance.

Heltec LoRa 32 Long Range Test 6:

For Range Test 6, this time I am going outside on the bike, and my brother will stay on the mountaintop until we finish the final test.

I will be stopping at different locations along the way, and we will see just how far this system can really go.

Let’s push it to the limit and find out what kind of range we can achieve in real-world conditions.

By the way, I am heading toward the riverside, because that’s the far end of our village; and it’s the perfect place to push this test even further.

Let’s stop here for a moment and check whether we’re still receiving data.

And wow; look at that; the mountain is clearly visible from here.

No way… this is amazing!

You can see the numbers are still coming in perfectly.

I checked the distance on Google Maps; 1,422 meters.

This is absolutely mind-blowing for a real-world test like this.

But I am not stopping here.

The next spot is the riverbank; and that’s where things are going to get even more interesting.

River side:

I have finally reached the river, and from here the mountain isn’t even visible anymore;

but here’s the good news; I am STILL receiving data.

This spot is actually a bit lower in elevation, so we had to lift the module up to maintain the signal.

From the top of the mountain, across the entire village, all the way down to the river; the signal has traveled an unbelievable distance.

The receiver is 1,951 meters away.

That’s almost 2 kilometers; and for this kind of real-world environment, with houses, terrain drops, and zero line of sight; this distance is insanely impressive.

This is not just long-range; this is next-level performance.

And from this point onward, I can’t go any further in this direction.

So now, I will have to head back to the main road and travel even farther out.

And this… is going to be the most extreme range test so far.