Internet Explorer 9 or IE9 (officially Windows Internet Explorer 9) is the ninth major version of the Internet Explorer web browser for Windows. It was released by Microsoft on March 14, 2011, as the successor to Internet Explorer 8. Microsoft released Internet Explorer 9 as a major out-of-band version that was not tied to the release schedule of any particular version of Windows, unlike previous versions. It is the first version of Internet Explorer not to be bundled with a Windows operating system, although some OEMs have installed it with Windows on their PCs. It was the last version to be called Windows Internet Explorer. The software was rebranded simply as Internet Explorer starting with the release of Internet Explorer 10.

Internet Explorer 9 supports ECMAScript 5 (ES5), several CSS 3 properties, and embedded ICC v2 or v4 color profiles support via Windows Color System, and has improved JavaScript performance. It was the last of the major web browsers to implement support for Scalable Vector Graphics (SVG). It also features hardware-accelerated graphics rendering using Direct2D, hardware-accelerated text rendering using DirectWrite, hardware-accelerated video rendering using Media Foundation, imaging support provided by Windows Imaging Component, and high fidelity printing powered by the XML Paper Specification (XPS) print pipeline. Internet Explorer 9 also supports the HTML media tags

History

Development

Development of Internet Explorer 9 began shortly after Internet Explorer 8 was released. Microsoft began taking features suggestions through Microsoft Connect soon after Internet Explorer 8 was released. The Internet Explorer team focused on improving support and performance for HTML5, CSS3, SVG, XHTML, JavaScript, hardware acceleration, and the user interface featuring agility and "a clean new design".

Microsoft first announced Internet Explorer 9 at PDC 2009 and spoke mainly about how it takes advantage of hardware acceleration in DirectX to improve the performance of web applications and improve the quality of web typography.

Later, Microsoft announced that they had joined the W3C's SVG Working Group, which sparked speculation that Internet Explorer 9 will support the SVG W3C recommendation. This was proven to be true at MIX 10, where they demonstrated support for basic SVG markup and improved support for HTML5. They also announced that they would increase the support greatly by the time the first Internet Explorer 9 Beta was released. The Internet Explorer team also introduced the new JavaScript engine for 32-bit Internet Explorer 9, codenamed Chakra, which uses Just-in-time compilation to execute JavaScript as native code. In mid-September 2011, the Acid3 test was revised to remove a few "antiquated and unusual" tests, and as a result, IE9 now passes the test with a score of 100/100.

At MIX 10, the first Internet Explorer 9 Platform Preview was released, which featured support for CSS3 and SVG, a new JavaScript engine called Chakra, and a score of 55/100 on the Acid3 test, up from 20/100 for Internet Explorer 8. On May 5, 2010, the second Internet Explorer 9 Platform Preview was released, which featured a score of 68/100 on the Acid3 test and faster performance on the WebKit SunSpider JavaScript benchmark than the first Internet Explorer 9 Platform Preview. On June 23, 2010, the third Internet Explorer 9 Platform Preview was released, which featured a score of 83/100 on the Acid3 test and a faster JavaScript engine than the second Internet Explorer 9 Platform Preview. The third Internet Explorer 9 Platform Preview also includes support for audio, video, and canvas tags, and WOFF. On August 4, 2010, the fourth Internet Explorer 9 Platform Preview was released, which features a score of 95/100 on the Acid3 test and a faster JavaScript engine than the third Internet Explorer 9 Platform Preview. On September 15, 2010, the Internet Explorer 9 Public Beta was released alongside Platform Preview 5, featuring a new user interface. In contrast to the previews, the Beta replaces any previously installed version of Internet Explorer. The sixth Internet Explorer 9 Platform Preview was released on October 28, 2010, and includes support for CSS 2D transforms and HTML semantic elements. The seventh Internet Explorer 9 Platform Preview was released on November 17, 2010, and features better JavaScript performance.

These previews were not full builds of Internet Explorer 9, as they were for testing the latest version of the MSHTML (Trident) browser engine. They were for web developers to send feedback on the improvements made, functioned in parallel with any other installed browsers, and were previews of the renderer technology only, containing minimalistic user interfaces and lacking traditional interface elements such as an address bar and navigation buttons. Microsoft updated these previews approximately every eight weeks.

On November 23, 2010, two updates for the Internet Explorer 9 Public Beta were released. KB2448827 brings improvements to reliability and fixes stability issues from the previous beta release. There are not much details of resolved issues disclosed by Microsoft. Moreover, KB2452648 resolves the in-built feedback issue with Internet Explorer 9 and the latest version of Windows Live Sign-in Assistant. These updates can be fetched from Windows Update or the Microsoft Download Center website. On the same day, Internet Explorer build 9.0.8027.6000 based on Internet Explorer 9 Platform Preview 7 was leaked. On February 10, 2011, the Internet Explorer 9 Release Candidate and Platform Preview 8 were released. The Release Candidate version featured improved performance, a Tracking Protection feature, a refined UI, support for more web standards, use of hardware accelerated graphics, and other improvements.

The final version of Internet Explorer 9 was publicly released during the South by Southwest (SXSW) Interactive conference in Austin, Texas, on March 14, 2011.

Release history

End of life

Support for Internet Explorer 9 on most Windows versions ended on January 12, 2016, when Microsoft began requiring customers to use the latest version of Internet Explorer available for each Windows version. For versions of Windows where Internet Explorer 9 was the final version of Internet Explorer available, support ended when support for that version of Windows ended. On January 14, 2020, Microsoft released the final regular IE9 update. However, IE9 (via Windows Server 2008) is eligible for the paid ESU (Extended Security Updates) and Premium Assurance programs. ESU security updates from Microsoft for IE9 were released until January 10, 2023 (January 9, 2024, for Azure customers) and Premium Assurance security updates will continue until January 13, 2026. Following which, only IE11 (the final version of Internet Explorer) will continue to be supported in any capacity.

Changes from previous versions

User Interface

Internet Explorer 9 includes significant alterations to its user interface when compared with previous versions. These include:

  • Pinned Sites: Integrates with the taskbar to make web site experience more like an application where users may "pin" a site and then return to it later like a shortcut. In the release candidate, users can pin a site and add more homepages to that site (e.g. pin Facebook and add Twitter as another homepage to that pinned site, so it would become a social program)
  • Security-enabled Download Manager: Manages file transfers and can pause and resume downloads and informs if a file may be malicious
  • Enhanced Tabs and Tab Page: the new tab page can show most visited sites, and tabs are shown next to the address bar (there is an option to have a separate row, like in Internet Explorer 8) with the feature of closing an inactive tab. Tabs can be "torn off" which means they can be dragged up and down to be moved from one IE window to another. This also ties in with the Aero Snap feature.
  • Add-on Performance Advisor: Shows which third-party add-ons may be slowing down browser performance and then allows the option to disable or remove them
  • Compact user interface, which includes the removal of the separate search box found in Internet Explorer 7 and 8. Also removed is the tab menu list found in Internet Explorer 8.

Scripting

JavaScript engine

Internet Explorer 9 (32-bit) features a faster JavaScript engine than Internet Explorer 8's, internally known as Chakra. Chakra has a separate background thread for compiling JavaScript. Windows runs that thread in parallel on a separate core when one is available. Compiling in the background enables users to keep interacting with webpages while Internet Explorer 9 generates even faster code. By running separately in the background, this process can take advantage of modern multi-core machines.

In Microsoft's preliminary SunSpider benchmarks for the third 32-bit Internet Explorer 9 Platform Preview, it outperformed the Internet Explorer 8 engine by a factor of 10 and also outperformed the newest Firefox 4.0 pre-release. Microsoft provided information that its new JavaScript engine uses dead code elimination optimization for faster performance, which included a small section of code in the SunSpider test as dead code. Robert Sayre, a Mozilla developer investigated this further, showing that Internet Explorer 9 Preview 3's dead code elimination had bugs, providing test cases exposing these bugs resulting in wrong compilation.

After its final release, 32-bit Internet Explorer 9 has been tested to be the leading mainstream browser in the SunSpider performance test.

The engine significantly improves support for ECMA-262: ECMAScript Language Specification standard, including features new to the recently finalized Fifth Edition of ECMA-262 (often abbreviated ES5). The Internet Explorer 9 browser release scored only 3 faults from 10440 tests in the Test262 Ecmascript conformance test (Ver. 0.6.2 5-Apr-2011) created by Ecma International.

The 64-bit version of Internet Explorer 9, which is not the default browser even on 64-bit systems, does not have the JIT compiler and performs up to 4 times slower.

DOM

DOM improvements include:

  • DOM Traversal and Range
  • Full DOM L2 and L3 events
  • getComputedStyle from DOM Style
  • DOMContentLoaded

CSS

Internet Explorer 9 has improved Cascading Style Sheets (CSS) support. The Internet Explorer 9 implementation report, which was created using Internet Explorer 9 Beta, shows Internet Explorer 9 passing 97.7% of all tests on the W3C CSS 2.1 test suite. This is the highest pass rate amongst CSS 2.1 implementation reports submitted to W3C.

CSS3 improvements include support for the following modules:

  • CSS3 2D Transforms
  • CSS3 Backgrounds and Borders
  • CSS3 Color
  • CSS3 Fonts
  • CSS3 Media Queries
  • CSS3 Namespaces
  • CSS3 Values and Units
  • CSS3 Selectors

HTML

HTML Media

Internet Explorer 9 includes support for the HTML media tags video and audio.

The audio tag will include native support for the MP3 and AAC codecs, while the video tag will natively support H.264/MPEG-4 AVC. Support for other video formats, such as WebM, require third-party plugins.

Canvas

Internet Explorer 9 includes support for the canvas element.

Inline SVG support

The first Internet Explorer 9 Platform Preview has support for:

  • Methods of embedding: inline HTML, inline XHTML, , full .svg documents
  • Structure: , , , ,
  • Shapes: , , , , , ,
  • Text
  • Filling, Stroking, (CSS3) Color
  • DOML2 Core and SVGDOM
  • Events
  • Presentation Attributes and CSS Styling
  • Transform definitions: translate, skewX, skewY, scale, rotate

    • SVG elements that are supported in the Platform Preview are fully implemented. Elements that exist in the Platform Preview have corresponding SVGDOM support and can be styled with CSS/presentation attributes.

    The final build of Internet Explorer 9 also supports:

    • Methods of embedding: ,