how to get the max bytes I can send in .net maui in BLE?

Question

I am using .net maui and in both android and ios how to get the max bytes I can send when I am connected to the device?

in BLE?

Answer 1

Hi @mc ,

Thanks for reaching out.

In BLE, you don’t have a single fixed “max bytes” value. It depends on the platform and the negotiated connection settings.

On Android, BLE uses an MTU (Maximum Transmission Unit). You can request a larger MTU at runtime, and once it’s negotiated, Android will tell you the actual size you can use. The usable payload is slightly smaller than the MTU itself, so you should always read the negotiated value and chunk your data accordingly.

On iOS, things are more restricted. iOS does not expose the MTU or allow apps to change it. The system decides the maximum write size for you. In practice, this is usually around ~20 bytes on older connections and up to ~182 bytes on newer ones. Because you can’t query this directly, the recommended approach is to assume a safe chunk size and split larger data into multiple writes.

So the solution on both platforms is:

• Always chunk your data before sending
• On Android, use the negotiated MTU to size your chunks
• On iOS, use a conservative fixed chunk size

Hope this helps! If my answer was helpful - kindly follow the instructions here so others with the same problem can benefit as well.

Answer 2

In .NET MAUI, when working with Bluetooth Low Energy (BLE), you can retrieve the maximum bytes you can send by checking the maximum transmit packet size for the underlying transport. For Android, you can use the BluetoothSocket.MaxTransmitPacketSize property, which returns the maximum supported transmit packet size. This can help you optimize the data you send to the connected BLE device.

For iOS, the approach may vary, but typically you would look for similar properties or methods in the iOS BLE APIs to determine the maximum transmission size.

Unfortunately, the specific implementation details for iOS are not covered in the provided context, so you may need to refer to the iOS documentation for BLE to find the equivalent property.

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References:

• BluetoothSocket.MaxTransmitPacketSize Property