Silverlight exceeds 50% penetration

According to RIAStats, a version of Silverlight is now detected on more than half of the browsers sampled! This is a telling milestone as installations of Silverlight continue to grow – drawing inexorably closer to that of Adobe Flash which currently enjoys installations on around 97% of browsers.

If you look at the graphic, and you consider the “not detected” section, it reads 49.99%, which means that the sum of those detected is better than half.


At PDC 2009 in November, Scott Guthrie announced that Silverlight penetration was up to around 45%, up from around 30% in the summer. These RIAStats numbers feel in line with that.

Of course, I know this doesn’t “prove” Silverlight is really on more than 50% of browsers, as RIAStats are not a perfect reflection of the web as a whole, but it seems an interesting milestone nonetheless.

Silverlight has been in the wild for 863 days: Silverlight was released for real (RTW, or “released to web”) on 05-Sep-2007, followed thirteen months later by Silverlight 2 RTW 14-Oct-2008, then less than nine months later we saw Silverlight 3 on 09-July-2009. Silverlight 4 is in beta – maybe Microsoft will announce its release at MIX10 in mid-March? If they do, that would be on a similar release rhythm as from Silverlight 2 to Silverlight 3.

Silverlight’s installed base will also get another boost from the 2010 Winter Olympics next month as well. (And Silverlight 2 shipped shortly after the 2008 Summer Olympics.)

It is interesting to note that another tracking site – – not only shows the penetration lower – and doesn’t agree on any of the numbers – but also doesn’t even agree on relative installed base across versions [EDIT: after Comment from Travis Collins, added in Silverlight 4 = 0.04 for RIAStats]:

RIAStats StatOwl
Silverlight 1 0.62 1.39
Silverlight 2 1.91 9.73
Silverlight 3 47.44 23.85
Silverlight 4 (beta) 0.04 (<1 pixel) not shown, or 0%
Undetected (reported) 49.99 65.03%

I’m not sure why they don’t agree – perhaps differences in sample sizes, sampling methodology, or due to different audiences being sampled.

Also, if you check the math yourself, you’ll see the values shown don’t tie down perfectly for RIAStats (though they do for StatOwl); if you add up the individual Silverlight versions along with the Undetected, you won’t get exactly 100%. Some sort of rounding errors I assume. [EDIT: See explanation in Comment from Travis Collins, RIAStats creator.] But I also assume that the Undetected = 49.99% is most likely right (at least not wrong due to a rounding error, since it is harder to round wrong there).

EDIT 01-Feb-2010: Found an interesting, relevant post on Cool facts about Silverlight penetration / mindshare from


5 thoughts on “Silverlight exceeds 50% penetration

  1. Travis Collins

    I made

    The difference between and is most likely due to polled audience. You’ll never find a report that’s of the total internet. So there will always be differences. If you look at the “Top Sites Column Chart” on, you’ll see that even those site’s Silverlight install base vary widely.

    The remaining .04 percent that’s not visible on the landing page pie chart is Silverlight 4. Its actually included in the Pie Chart, but .04% is less than one pixel wide even at a very large radius. You can see the Silverlight 4 representation in the “Major Versions Line Chart”; mouse over the lines at the bottom.

    You can add the polling script to your site, and get a free daily personalized RIAStats report. Adding the polling script will help you understand your user base, and help the community further its understanding of these topics.

    Glad you found RIAStats useful!

    Travis Collins

  2. Kevin Nasby

    Hi, I found this post while looking for help with fixing Microsoft Silverlight. I’ve recently changed browsers from Safari to Microsoft IE 6. Now I seem to have a problem with loading sites that have Microsoft Silverlight. Every time I browse page that requires Microsoft Silverlight, the page does not load and I get a “npctrl.dll” error. I can’t seem to find out how to fix it. Any aid getting Microsoft Silverlight to work is very appreciated! Thanks

  3. Nick

    I am really fascinated where everyone seems to be gettting their Silverlight stats. We are itching to redevelop large e-commerce booking engines in Silverlight but to date with our own internal tracking system, only 32% of retail Mum & Dad users have it installed on their machines. We have very high traffic and many unique visitors so the average is fairly acurate….well for our sector anyway. We have scratched Silverlight for 2010 and are targetting 2011/2012 if ever. Why can’t Microsoft force Silverlight out through automatic updates instead of leaving as optional update?????

    1. Bill Wilder Post author

      @Nick – Re: “but to date with our own internal tracking system, only 32% of retail Mum & Dad users have it installed on their machines” – I think your own stats may be your best, though the overall trending is relevant. One thought though – the 32% represents those with Silverlight already running, but is a smaller number than those *willing* to use Silverlight because many users will download the player if it helps them interact with a site. Of course, willingness depends on many factors – not all sites are the Olympics.

      Re: “Why can’t Microsoft force Silverlight out through automatic updates instead of leaving as optional update” – I don’t know, but perhaps if they did they would take heat from anti-trust folks?

  4. Dave

    I call BS on

    Unless I’m getting all of the non-Silverlight visitors, the silverlight enabled browser numbers displayed on ria stats is not accurate.


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