Microsoft's venerable Internet Explorer browser lost its majority position last month, according to a Web metrics vendor, falling under the 50% bar for the first time since it thrashed Netscape Navigator and assumed control of the browser market.
By the estimates of Irvine, Calif.-based Net Applications, Internet Explorer (IE) ended 2015 with a user share -- a measurement of unique visitors to the websites of the company's clients, and one of the few proxies for real-world browser adoption -- of 48.6%. That was a drop of 1.5 percentage points from November, the largest one-month contraction in IE's share since October 2011.
At one point, IE held a user share as large as 89.4% in Net Applications' tracking. That was in January 2005, when Computerworld began recording the firm's metrics.
IE's share had been even higher earlier in the decade, after it had forced Netscape out of the market in the early 2000s, and before Mozilla took up Netscape's mantle with Firefox in 2004. Firefox was the first browser to challenge IE's dominance of the browser space, and was widely adopted by those who viewed the then-IE6 as stuck in the past.
Microsoft responded to the threat from Firefox with a series of improved browsers -- IE7 in 2006 for Windows Vista's launch, IE8 in 2009 preceding the debut of Windows 7, and others -- but its user share decline continued. IE flirted with falling below the 50% mark in late 2011; in October of that year, it posted a user share of 51.9%. But the browser recovered some of that lost share, scratching its way to 58.9% in November 2014.
Since then, however, it's been all downhill for IE.
The biggest factor in IE latest contraction was Microsoft's abrupt decision in August 2014 to require most users to upgrade to 2013's IE11. By demanding that users upgrade from, say, IE8 to IE11, Microsoft motivated customers to download and run a rival browser, since people had to change in any case.
The mandate was disastrous for IE: In the last 12 months, it shed 10.5 percentage points of user share, an amount representing an 18% shrinkage.
The biggest beneficiary of IE's decline has been Google's Chrome, which during the past year has added 9.7 percentage points to its tally, ending December with a user share of 32.3%.
Meanwhile, Firefox has languished in the last 12 months, seemingly stuck in a range between 11% and 12%. Firefox's December share was 12.1%.
Nor has Edge, Microsoft's latest browser, made a difference. (Net Applications tosses Edge's share into the overall IE bucket, so the 48.6% for December included the 2.3% attributed to Edge.) Windows 10 users have largely rejected Edge -- the browser's share of the Windows 10 user base continues to fall -- even though Microsoft went to great lengths to push customers toward the browser, including changing the OS's default browser to Edge after Windows 7 and Windows 8.1 users upgraded to Windows 10.
If the 12- and 3-month trends shown by Net Applications' data persist, IE will slip below 45% by April or May.
Previously, IE's position as the No. 1 browser seemed safe, in large part because it was the standard for businesses, particularly enterprises and other large organizations. But even that stronghold has been breached by Chrome, which will be the primary browser for two-thirds of enterprise users this year.
If that forecast by Gartner is realized, IE may slip to the No. 2 spot. Net Applications' 12-month average increase/decrease for Chrome and IE imply that the switch in positions -- with Chrome become the top browser dog -- could occur as soon as October.