Is Bluetooth faster than Wi-Fi?

Question

I notice that on my iPhone, when I use my personal hot-spot to distribute Wi-Fi, if I have Bluetooth enabled, the phone will make a Bluetooth connection to my laptop instead of a Wi-Fi connection.

So I'm wondering:

Is Bluetooth faster than Wi-Fi?

Solution 1

The Bluetooth standard maximum data rate is at best 3Mbps or about 2.1 after protocol overheads take their cut.

Wi-Fi on the other hand maxes anywhere from 54 to 1300+Mbps depending on whether you have "g", "n", or "ac" Wi-Fi and what enhancements the adaptors and router support.

So no. Bluetooth is not faster than Wi-Fi. Not even vaguely close.

Bluetooth v3 and v4 have higher data rates but the actual data transfer in those implementations happens over Wi-Fi; Bluetooth is only used to set up and negotiate the connection.

Solution 2

For the purpose of tethering a notebook to the internet via a mobile phone in the field, the most important difference is power consumption and range.

The Wifi tether can consume your smartphone's battery in an hour, while with the Bluetooth tether you can go for hours, and the phone will not shut itself down before the notebook does.

So what can each kind do and not do, besides the power requirement difference?

Wifi:

• Higher speed (which you will probably NOT be able to exploit at all, since the mobile link is much slower, typically less than 3Mbps effective even on 3G).
• More clients connected simultaneously. The only limit is the number of clients the phone can handle; typically 8.
• Wider coverage. Depends on the phone aerials, typically 50m in the open are no problem.

Bluetooth:

• About 3Mbps link between the client and the phone.
• ONLY ONE client at a time (even if you have BT 2.0+ which supports multiple connections).
• Range of up to 10 meters.

So when to use which one? From the above it should be obvious:

• Bluetooth: when you're the only one who needs to use the internet, or when the battery life is a concern.
• Wifi: when you can use wall power for both the client and the phone, when you need to connect multiple clients, or when you need to use your phone as an AP to (for example) Chromecast a movie to a TV/projector. If you use for example, a VideoStream application for Chrome, you only need the internet for connecting to the Chromecast, and from there on the stream only flows from your computer to the Chromecast, so the slow outward connection will not be a problem.

Comments

[supercat]

Bluetooth may not support as high a data rate as WiFi, but on the flip side it seems able to establish connections more quickly. From what I understand of wireless radio protocols, being able to exchange data over a low-speed connection may help establish the synchronization necessary for a faster one; is it possible that BlueTooth might be used for such a purpose?

[Cornstalks]

@supercat: Bluetooth 3.0 + HS actually just uses Bluetooth to do a handshake and establish a connection, and then uses 802.11 frames (i.e. Wi-Fi) to transfer data (so it's like a Bluetooth + Wi-Fi connection).

[Gary - Stand with Ukraine]

Bluetooth tends to use much less power than Wi-Fi. On a 3G connection, the higher speed of Wi-Fi isn't really necessary.

[Alex KeySmith]

+1 from me regarding the power usage. But we should also bare in mind of 4g possibly exceeding the bluetooth speed.

[Alex KeySmith]

True it certainly depends on many conditions, but just to mention it - as I've heard people getting 20 MB/s (not me I'm in the countryside!). However in many cases whilst out and about, it's going to be better to save battery life life than get a faster connection. So I'd personally use bluetooth anyway.

[Marek Staněk]

exactly my point. it doesn't help you if you download a page in 100ms instead of a second, when it kills your connection in an hour when you need to work for three hours plus.

[endolith]

"happens over Wi-Fi" Does that mean they both need to be connected to the same Wi-Fi router, or do they form an ad-hoc network?

[David Ferenczy Rogožan]

I would update your answer for the year 2018: in Czech republic, LTE is pretty common, the coverage is good and it's much faster than what Bluetooth allows. So use the Bluetooth tethering only in case you need more energy efficient technology.