

How to measure page load time with google analytics - jrosoff
http://blog.yottaa.com/2010/10/how-to-measure-page-load-time-with-google-analytics/

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pierrefar
Just a heads up, and the post notes this, that this way of timing is already
well into the page load sequence: the server has received the request, built
the HTML and has started sending it, and the browser is already parsing it.

Also, be careful with when different browsers fire the onLoad event. For
example, Safari 3: <http://www.howtocreate.co.uk/safaribenchmarks.html>

Overall though, a cool hack even with the caveats above as it could give you
actionable data.

Another good source of loading time metrics is Google Webmaster Tools. They
have two metrics, one in the download time in the Crawl Stats section the Site
Performance metric in the Labs section. Combined, they give you a really good
insight into how your website is doing over time. A good game to play is spot
the (very clear) inverse relationship between the number of pages crawled vs
download time.

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jrosoff
Yes definitely some issues with measuring page load time this way. It is
useful data to get started with. The web timing API will make this data much
better, but it's still early (it's in IE9 and some early developer builds of
chrome and firefox). Once this API is more widely deployed, this is the right
way to measure performance as it allows you to take into account navigation
time as well as rendering time.

Google Webmaster Tools does indeed give you a good perspective on performance.
I believe this data comes from the google toolbar (can someone confirm this?).
My problem with the data reported by webmaster tools is that it's an average.
It doesn't tell me what the _worst_ page load time of the _best_ page load
time my users are experiencing.

As a shameless plug, you can also check out our own tools from yottaa:
<http://www.yottaa.com> that give you a bunch of detailed information about
your websites performance. I think tools like these complement the approach
detailed in the post.

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jacquesm
If after timing your page you want to get some external confirmation I use
this site frequently:

<http://www.websiteoptimization.com/services/analyze/>

It gives some pretty useful results when you're tuning your page because it
breaks it down in to components.

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jrosoff
Cool! There are a bunch of external monitoring services that are worth
checking out in addition to this..

\- <http://www.yottaa.com> (shameless plug for my own company) \-
<http://www.webpagetest.org> \- <http://www.zoompf.com> \-
<http://www.showslow.com>

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lazyant
Hello, just a questions about yottaa.com: on my firebug Yslow(V2) I get an
Overall performance score 91 (and in Page Speed I get 95). How come on yottaa
I get a YSlow score of 78?

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jrosoff
What site are you measuring? I'll go check it out. Feel free to follow up via
jrosoff AT yottaa DOT com

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JangoSteve
Be sure to post the findings/reason here.

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rarestblog
Clever idea!

Although I prefer Chrome Dev Tools for this task - measuring page load time of
people with different connection speeds, CPUs (for rendering), browsers seems
a little weird.

The graph about bounce rate caught my attention. Although the author draws a
straight line, it looks more like a parabola with minimum around 3.5 seconds.
Which is kind of unexpected (and I can't even think of any reasonable
explanation for this).

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lukestevens
This is a nice idea, so points for ingenuity.

There are a few small problems though:

\- Page 'load' time is a bit ambiguous, I'd prefer page 'rendering' time,
perhaps. (The author does note the limitation of this approach.)

\- Time to window.onload may be a _very_ long time in some environments,
especially when 3rd party scripts are present, especially (if memory serves)
in IE.

\- From eyeballing the "Bounce rate by page load time" the linear trend placed
on top seems dubious -- if anything bounce rate seems to drop until the 3700ms
mark. (The author notes in the text however that users seem tolerant up to the
5000ms mark).

Quibbles aside, having more page rendering time data correlated to bounce rate
is an excellent idea, as I've seen some posts in web design land get pretty
carried away with n-th degree optimization because they read speed matters for
Google and Amazon.

In my experience, I optimized a site's page rendering time dramatically,
expecting a bump in average pages per visit, and saw absolutely no change
whatsoever. We need more data :)

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theDoug
A lot of things are being pushed into GA that aren't entirely appropriate for
it, but I'm glad people are still curious in trying these things out.

~~~
lukestevens
Yes, I agree. GA is being used more and more as an ad-hoc analytics data store
these days, and hopefully with some creative uses of the GA API we'll see more
interesting uses that negate the need to use Excel.

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dpapathanasiou
If you're interested in more aspects of web page performance, Show Slow
(<http://www.showslow.org/>) is a good tool.

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coachwei
Like the result from the article. Showing the page load time vs percent of
users is a very useful way to analyze site performance:how many percentage of
site users are experiencing slow performance?

Further, combing this with web timing API would be even more interesting.

