Siri's Impact on Data Usage Examined

With the release of the new Siri intelligent assistant on the iPhone 4S, some users have been curious about how much data the feature uses given that most users are on limited data plans and that Siri must communicate with outside servers in order to function. Ars Technica has now taken a look at a set of common Siri tasks, determined that those specific queries used an average of 63 KB of data.

siri icon on linen
The testing was broken down into two groups of queries, with the first being local queries requiring data only to interpret the spoken input. Data usage on those queries came in at an average of approximately 36.7 KB.

We performed six tasks that would be considered to be local tasks. These queries included things like, "Set an alarm for 3 hours from now," "Make an appointment for 2pm on Friday" (and then telling Siri to cancel the task), "Remind me to file expense reports when I get home," and "What is the contact info for Ars Technica?"

These tasks added up to a total of 220KB of data usage, or an average of 36.7KB per query. The actual numbers ranged from 60KB down to 18KB, and we believe this is correlated to the complexity of the specific query and language we used to perform it.

For more complex queries bringing results back from the Internet via Wolfram Alpha or Google, the average was 94.7 KB, with a range of 23 KB to 187 KB.

Summing up the data usage, Ars Technica calculated that a user performing all eleven of the sample queries via 3G every single day would consume approximately 20 MB of data in a month. Informal surveys of typical Siri usage revealed that even high-use customers tend to come in at about fifteen queries per day, which would represent in the neighborhood of 30 MB of data per billing cycle depending on complexity of requests.

Most carriers offer customers easy ways to check their current and historical data usage, helping them gauge how much cap space they typically have as they consider how Siri usage will affect their data needs.

Related Forum: iPhone

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Top Rated Comments

bettaboy123 Avatar
176 months ago
30 MB a month isn't too bad at all. :)
Score: 12 Votes (Like | Disagree)
Eager Beaver Avatar
176 months ago
Love my 4S but I don't really use Siri for much other than "Call John Doe" tasks, once in a while. Am I the only one who is so luke warm about this feature??




I've used it daily since new, and find myself using it more and more.
What a great tool siri is ......... set a reminder for tomorrow 11am, message Tom, "Ill b there in an hour", call napa, remind me to put the defrosted ground beef in the refrig when I get home, .................... oops, gotta run, the timer siri set for me just went off, I have to leave to go meet my friend.

Being able to push and hold 1 button, and then tell siri to do things (while I am busy myself, doing things with my other hand and not wanting to scroll thru my iphone with two hands trying to send Tom a message.

Siri is the ONLY reason i bought this bs iphone 4, and I'm actually very impressed with her.
Score: 11 Votes (Like | Disagree)
SafariX Avatar
176 months ago
Not a lot of data being used. Who cares
Score: 10 Votes (Like | Disagree)
AriX Avatar
176 months ago
Good research. Thanks Ars.
Score: 10 Votes (Like | Disagree)
atticus18244fsa Avatar
176 months ago
Doesn't that mean that a heavy user (and using Siri only 15 time a day is not really that heavy) would use 900 MB+ of data per month just using Siri? With AT&T and Verizon switching to 2GB caps, that means have your data is used up just from using Siri. :eek:

Maybe Apple needs basic commands like setting appointments and alarms to be integrated in iOS so those commands don't have to go through the internet. :)

30MB per month not per day.
Score: 8 Votes (Like | Disagree)
StyxMaker Avatar
176 months ago
It sounds excessive, but most people are in wi-fi zones during the day. Most offices, schools, college campuses, hospitals, airports, even shoppings malls are all wi-fi enabled (and mostly free).

And if Siri is the only person you talk to while sitting in rush hour traffic, then you've got bigger problems than your data plan.
Only Siri, and the voices in my head. Sometimes it's hard to tell the difference. I think Siri is getting jealous, she told me I had to stop talking to the other voices.
Score: 7 Votes (Like | Disagree)