Browser wars

What the term means

Browser wars is the common name for the competition among software companies to have their web browser used by the most people. A browser is the program that fetches web pages and displays them.

This entry treats the contest in two rounds. In the first, from 1995 to about 2001, Microsoft’s Internet Explorer overtook Netscape Navigator, and the contest became a central subject of a U.S. antitrust case.¹² Antitrust law is the body of law that limits how companies may gain or keep market power.

In the second round, beginning in 2003, Apple’s Safari, Mozilla Firefox and Google Chrome took users from Internet Explorer.³⁴⁵

The phrase was still in use in 2012. When Chrome passed Internet Explorer that year, StatCounter’s chief executive, Aodhan Cullen, said “the browser wars are back with a vengeance.”⁵

This entry sets out what courts, regulators and the companies themselves documented. Where the parties disagreed, both positions are given, with the source for each.

Netscape’s head start (1994 to 1995)

Netscape Communications shipped version 1.0 of Netscape Navigator on December 15, 1994. It ran on Microsoft Windows, the Apple Macintosh and Unix computers using the X Window System.⁶

A single commercial license cost $39, and the browser was free for academic, nonprofit and evaluation use, downloadable over the internet.⁶ Netscape launched it alongside its Netsite server software, priced at $1,495 and $5,000, and presented the browser and servers together as a complete, secure system for doing business online.⁶ The announcement was posted to the www-talk mailing list by Netscape co-founder Marc Andreessen.⁶

Navigator quickly became the most-used browser. Estimates that Microsoft executives cited at trial and relied on in business planning, the trial court found, put Navigator above 80% of browser usage in January 1996.¹

The court’s own summary used a lower starting figure for Navigator, above 70% in early 1996. Both numbers appear in the findings.¹

The trial court found that Navigator ran on many operating systems, and that Microsoft chairman Bill Gates warned internally that Netscape was “pursuing a multi-platform strategy.”⁷

That mattered because of middleware: software that runs on top of an operating system and offers its own programming interfaces to other programs. The appeals court later described Navigator and Java as middleware products written for multiple operating systems.²

In principle, developers could write programs for those interfaces instead of for Windows. The trial court found that this threatened what it called the applications barrier to entry.⁷

The court described that barrier as a cycle. Users choose the operating system with the most applications, and developers write first for the operating system with the most users, which makes it hard for a new system to attract either.⁷

Microsoft’s response (1995 to 1998)

Microsoft introduced its browser, Internet Explorer, in July 1995, according to the trial court, which found the first version demonstrably inferior to Netscape’s browser of the time.⁷

Microsoft then invested heavily. The court found that from 1995 onward it spent more than $100 million a year on Internet Explorer, and that the team grew from five or six developers in early 1995 to more than a thousand by 1999.⁷

Reviews improved. Reviewers praised Internet Explorer 3.0, released in late 1996, and by Internet Explorer 4.0, in late 1997, reviewers were roughly split between it and Navigator, the court found.⁷

The Internet Explorer 3.0 beta, announced on May 29, 1996, added ActiveX controls (small programs that run inside the browser) and scripting in both Visual Basic Script and JavaScript, and Microsoft said the next beta would include a Java virtual machine.⁸

Microsoft built its version of Netscape’s scripting language, called JScript, starting in October 1995. Its engineers tested it against thousands of websites to match how Netscape’s browser behaved.⁹ The lack of a formal specification for the language was a constant problem for that team, and its leader raised the issue repeatedly with Netscape.⁹

The June 1995 meetings

The trial court also made findings about two meetings in June 1995. It found that at meetings on June 2 and June 21, Microsoft proposed that Netscape stop developing platform-level browsing software for Windows 95 in exchange for a special relationship with Microsoft.⁷

The court also found that Microsoft said it would treat Netscape as a competitor if Netscape marketed Windows 95 browsing software built on different technologies, and that Netscape declined.⁷

After the June 21 meeting, the court found, Microsoft delayed giving Netscape a technical interface it had asked for until late October 1995, more than three months later.⁷

Price and distribution

Microsoft never charged for a separately distributed Internet Explorer license, and its senior executives decided not to raise the price of Windows 95 when the browser was included, the court found.⁷

The pricing decision came early. In early 1995, the court found, Internet Explorer developers had considered charging computer makers for the browser as an add-on to Windows 95, and senior executives chose not to.⁷

In summer 1997 some mid-level employees proposed charging for parts of Internet Explorer 4.0. Senior executives rejected the idea, and Microsoft executive Paul Maritz said that raising browser share to 50% or more was still the major goal.⁷

The court concluded that protecting the applications barrier, rather than any plan to profit from the browser itself, was the main reason Microsoft set the price at zero.⁷

The court found that Microsoft also licensed the browser free to internet access providers, software developers and Apple. It offered America Online (AOL) placement inside Windows in return for promoting Internet Explorer over Navigator.⁷

The appeals court later described one term of the AOL deal: AOL agreed it would not supply more than 15% of its subscribers with a browser other than Internet Explorer.²

Microsoft’s own position was that Internet Explorer was not a separate product at all. A December 1997 Microsoft statement on the dispute described it as an integrated feature of Windows.¹⁰

The shift in usage

The trial court’s figures show how quickly usage moved. Data from the firm AdKnowledge put Internet Explorer at 20% in January 1997 and 49% in August 1998, while Navigator fell from 77% to 48%.¹

New users moved faster. In the last six months of 1997, 57% of new browser users chose Internet Explorer and 39% chose Navigator, the court found.¹ A February 1998 measure found that Internet Explorer was used on 62% of new internet connections made over the previous six months.¹

The court summarized that from early 1996 to late summer 1998, Internet Explorer rose from about 5% to about 50% of usage.¹

It found that superior quality was not responsible for the rise, and that without Microsoft’s other measures to maximize Internet Explorer’s usage, Navigator would not have lost so much share. It quoted a February 1998 internal Microsoft presentation saying many customers saw the two browsers as “parity products.”¹

The court also found that Internet Explorer’s features never surpassed Navigator’s by enough to move a significant part of Navigator’s existing users.¹

Looking ahead, the court’s most reasonable prediction was that by January 2001 Internet Explorer would have more than 60% of usage and Navigator less than 40%.¹

United States v. Microsoft (1998 to 2002)

The U.S. Department of Justice sued Microsoft on May 18, 1998, in the U.S. District Court for the District of Columbia. A group of states, led in the caption by New York, brought a parallel case that was consolidated with it.¹¹⁷

The trial ran from October 19, 1998, to June 24, 1999.⁷ On November 5, 1999, Judge Thomas Penfield Jackson issued his Findings of Fact, the court’s formal statement of what it had concluded happened.¹¹¹²

The findings held that Microsoft had monopoly power in operating systems for Intel-compatible personal computers. They cited a market share above 90% every year for a decade, a high barrier to entry and the lack of a commercially viable alternative to Windows.⁷

Microsoft’s case

Microsoft disputed the government’s account. In court papers filed on December 23, 1997, during an earlier phase of the dispute, it argued that the files that make up Internet Explorer were an integral part of Windows 95 and could not be removed without degrading the system.¹⁰

Microsoft also rejected the idea of simply hiding the browser while leaving its files in place. Its press statement that day quoted the company’s legal memorandum: “removing the icon from the desktop is like putting a plate over a car radio.”¹⁰

After the findings were issued, Bill Gates said Microsoft would keep making its best efforts to resolve the case, and he indicated that preserving its right to add features to its products would be a key condition in any settlement.¹²

Judgment and appeal

The trial court issued its Conclusions of Law on April 3, 2000, and a Final Judgment on June 7, 2000. That judgment required Microsoft to submit a plan to split itself into an operating systems company and an applications company.²

On June 28, 2001, the U.S. Court of Appeals for the D.C. Circuit, sitting en banc (as a full court rather than a three-judge panel), issued an unsigned opinion for the court.²

The appeals court upheld the finding that Microsoft had illegally maintained its operating system monopoly, though not every act the trial court had condemned. It also reversed the finding that Microsoft had attempted to monopolize the browser market.²

On the tying claim, the charge that Microsoft illegally bundled the browser with Windows, the appeals court ruled that the automatic per se rule (which treats some conduct as illegal without weighing its effects) was inappropriate, and sent the claim back for further proceedings.²

It vacated the breakup order and required that the case go to a different trial judge. The court cited the trial judge’s private contacts with the press and offensive public comments, which it said created an appearance of partiality.²

Settlement

Microsoft signed a consent decree, a court-approved settlement, with the U.S. government on November 2, 2001. Its announcement said the restrictions would last five years.¹³

The restrictions covered how Microsoft develops and licenses software, how it works with independent software makers and how it shares technical information with partners and competitors.¹³

Bill Gates called the settlement fair and reasonable and said it was in the best interests of consumers and the economy.¹³ The court entered the Final Judgment on November 12, 2002, and a modified version on September 7, 2006.¹¹

Netscape becomes Mozilla (1998 to 2005)

On January 22, 1998, Netscape announced that it would post the source code (the human-readable program text) of its next browser, Communicator 5.0, free on the internet.¹⁴

The same release made Navigator and Communicator 4.0 Standard Edition free for all users from that day. Chief executive Jim Barksdale said “the time is right for us to take the bold action of making our client free.”¹⁴

Netscape announced mozilla.org, a dedicated team and website to coordinate the open-source project, on February 23, 1998.¹⁵ Mozilla says the release was meant to harness the creative power of thousands of programmers on the internet.¹⁶

The project soon changed course. On October 26, 1998, Brendan Eich published a roadmap that set out plans to drop the old Communicator code base and build on new technology instead.¹⁵

America Online agreed to buy Netscape in a merger agreement dated November 23, 1998, and completed the acquisition on March 17, 1999, converting each Netscape share into 0.9 of an AOL share.¹⁷

The open-source project took years to produce a finished browser. Mozilla 1.0, the project’s first major version, was released in 2002, as was the first version of a separate browser called Phoenix, later renamed Firefox.¹⁶

The Mozilla Foundation, an independent nonprofit, was announced on July 15, 2003. Mozilla’s archive records that AOL cut its remaining Mozilla developers the same day.¹⁵¹⁶

The foundation released Mozilla Firefox 1.0 on November 9, 2004, for Windows, Mac OS X and Linux. It said more than eight million people had downloaded the preview release in the previous month.⁴

By early 2004 the browser was called Mozilla Firebird; on February 9, 2004, it was renamed Mozilla Firefox.¹⁵

Firefox 1.0 offered tabbed browsing, pop-up blocking and built-in search. Mozilla says Firefox passed 100 million downloads in less than a year.⁴¹⁶

On March 10, 2005, the foundation said it would stop official releases of the older Mozilla Application Suite, and on August 3, 2005, it announced the creation of the Mozilla Corporation.¹⁵

The second round (2003 to 2012)

Apple entered on January 7, 2003, with a free public beta of Safari for Mac OS X. Safari was built on KHTML, the rendering engine (the part that turns HTML and CSS into a visible page) of the open-source KDE project’s Konqueror browser.³

Apple said it would contribute its changes back to the open-source community, and claimed Safari loaded pages more than three times faster than Internet Explorer for Mac.³

In 2004, people from Apple, the Mozilla Foundation and Opera Software founded the WHATWG (Web Hypertext Application Technology Working Group).¹⁸

The group said it was concerned about the W3C’s direction with XHTML, its lack of interest in HTML and what it saw as disregard for the needs of working web developers.¹⁸

Google announced Google Chrome on September 1, 2008, and released a beta for Windows in more than 100 countries the next day.¹⁹

Chrome ran each tab in its own protected environment, so that one crashing page would not take down the others. Google said it would release all of Chrome’s code as open source.¹⁹

Google credited other open-source projects, including Apple’s WebKit and Mozilla’s Firefox, as sources of components. Chrome also introduced V8, a new JavaScript engine that Google described as more powerful than existing ones.¹⁹

The European browser choice screen

In January 2009 the European Commission sent Microsoft a Statement of Objections, a formal list of preliminary charges. Its preliminary view was that tying Internet Explorer to Windows may have breached the EU’s ban on abuse of a dominant position, then Article 82 of the EC Treaty and now Article 102 of the Treaty on the Functioning of the European Union.²⁰²¹

The Commission’s documents give two dates for that statement. The decision says January 14, 2009, and the press release says January 15.²⁰²¹

On December 16, 2009, the Commission made commitments offered by Microsoft legally binding and closed the proceeding, without concluding whether Microsoft had broken EU competition law.²⁰

The Commission’s press release said its preliminary view was that the tying gave Internet Explorer a distribution advantage on more than 90% of personal computers. Breaking the commitments could bring a fine of up to 10% of Microsoft’s annual turnover.²¹

Microsoft agreed to show a Choice Screen, through Windows Update, to users in the European Economic Area of Windows XP, Vista and 7 who had Internet Explorer as their default browser.²⁰

The screen listed up to 12 browsers, five prominently and seven more by scrolling, in random order each time. On Windows 7, computer makers and users could also turn Internet Explorer off, and the commitments ran for five years.²⁰

Competition Commissioner Neelie Kroes said “millions of European consumers will benefit from this decision.”²¹

The screen did not always appear. On March 6, 2013, the Commission fined Microsoft 561 million euros after Microsoft acknowledged that it had not been shown to Windows 7 Service Pack 1 users from May 2011 to July 2012.²²

The Commission said about 15 million Windows users in the EU missed the screen in that period. By November 2010, it said, there had been 84 million browser downloads through it.²²

Chrome takes the lead

The web analytics company StatCounter reported that in May 2012, Chrome passed Internet Explorer worldwide for a full calendar month for the first time.⁵

Its figures were 32.43% for Chrome and 32.12% for Internet Explorer, with Firefox at 25.55%. StatCounter noted that Chrome had gone from zero to market leader in less than four years.⁵

Internet Explorer’s retirement (2020 to 2022)

Microsoft rebuilt its newer browser, Microsoft Edge, on Chromium, the open-source project that Chrome is built on. Microsoft released the new Edge on January 15, 2020, in more than 90 languages.²³

Microsoft said the change was meant to improve compatibility for users and reduce fragmentation for web developers, and that it would work with the Chromium community.²³

On June 15, 2022, Microsoft retired Internet Explorer 11 on certain versions of Windows 10, ending a product line that had lasted more than 25 years. Windows 11 had already removed it.²⁴

Opening Internet Explorer on those systems now opens Edge instead. Edge includes an IE mode for older sites, and Microsoft has committed to supporting that mode through at least 2029.²⁴

The browser market today

As of September 2026, StatCounter put Chrome at 66.36% of browser use worldwide, followed by Safari (18.27%), Edge (6.04%), Firefox (2.8%), Samsung Internet (2.31%) and Opera (1.77%).²⁵

On desktop computers alone, Edge is second, at 14.64% to Chrome’s 65.09%, followed by Safari (8.06%) and Firefox (6.11%).²⁶ In the United States, Safari’s share is higher: 30.42% in September 2026, against Chrome’s 53.82%.²⁷

Phones now account for most browsing. StatCounter put mobile devices at 58.99% of worldwide page views in September 2026, desktop computers at 39.26% and tablets at 1.76%.²⁸

Apple’s App Store rules require apps that browse the web on iPhone and iPad to use Apple’s WebKit framework. Developers can apply for permission to use a different browser engine in the EU and Japan.²⁹

Competition questions have continued. In United States v. Google, a search case, Judge Amit P. Mehta issued a remedies ruling on September 2, 2025.³⁰³¹

The ruling barred Google from exclusive contracts covering the distribution of Search, Chrome, Google Assistant and the Gemini app, and from stopping partners from distributing rival browsers.³⁰ The court denied the government’s request to force Google to sell Chrome.³¹

The ruling also required Google to share certain search index and user-interaction data with some rivals, and to offer search and search text ads syndication to certain competitors.³⁰

How each side described it

The government’s case, as accepted by the trial court, was that Microsoft used its control of Windows to keep Navigator and Java from growing into platforms that could weaken its operating system monopoly.⁷²

Microsoft’s case was that the browser was part of Windows, that removing it would harm the operating system, and that the 2001 settlement served consumers and the economy.¹⁰¹³

The appeals court accepted parts of each. It upheld liability for maintaining the operating system monopoly, but reversed the attempted monopolization finding, rejected the automatic tying rule and vacated the breakup.²

In Europe the tying case ended with commitments made binding under Article 9 of Regulation 1/2003, and the later fine concerned Microsoft’s failure to honor those commitments.²¹²²

Netscape’s documented response in the market was to make its browser free and release the source code that became Mozilla.¹⁴¹⁶

Timeline

1. September 2, 2025U.S. court bars Google's exclusive distribution deals for Search and Chrome but denies a Chrome sale³⁰
2. June 15, 2022Microsoft retires Internet Explorer 11 on certain Windows 10 versions²⁴
3. January 15, 2020Microsoft releases the new Edge, built on Chromium²³
4. March 6, 2013European Commission fines Microsoft 561 million euros over the missing choice screen²²
5. May 2012Chrome passes Internet Explorer worldwide for a full month (StatCounter)⁵
6. December 16, 2009European Commission makes Microsoft's browser choice screen commitments binding²⁰
7. September 2, 2008Google releases the first Chrome beta for Windows¹⁹
8. November 9, 2004Mozilla Foundation releases Firefox 1.0⁴
9. July 15, 2003Mozilla Foundation announced as an independent nonprofit¹⁵
10. January 7, 2003Apple releases the first public beta of Safari³
11. November 12, 2002Court enters the Final Judgment settling the U.S. case¹¹
12. November 2, 2001Microsoft signs a consent decree with the U.S. government¹³
13. June 28, 2001D.C. Circuit upholds monopoly maintenance liability and vacates the breakup order²
14. June 7, 2000Trial court's Final Judgment orders a plan to split Microsoft into two companies²
15. November 5, 1999Judge Thomas Penfield Jackson issues the Findings of Fact¹¹
16. March 17, 1999America Online completes its acquisition of Netscape¹⁷
17. May 18, 1998U.S. Department of Justice sues Microsoft¹¹
18. January 22, 1998Netscape announces it will release its browser source code and makes Navigator free¹⁴
19. July 1995Microsoft introduces Internet Explorer (date per the court's findings)⁷
20. December 15, 1994Netscape ships Navigator 1.0⁶

What it means for your website

See also

• Netscape Navigator (coming soon)
• Internet Explorer (coming soon)
• Mozilla Firefox (coming soon)
• Google Chrome (coming soon)
• JavaScript
• Web browser (coming soon)
• Responsive design
• How does a website work

References

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2. United States v. Microsoft Corp., Nos. 00-5212 and 00-5213, opinion of the U.S. Court of Appeals for the D.C. Circuit. U.S. Department of Justice. 2001-06-28. accessed October 22, 2026.
3. Apple Unveils Safari. Apple Newsroom. 2003-01-07. accessed October 22, 2026.
4. Open Source Software Driving Innovations in Web Experience (Firefox 1.0 release). Mozilla Foundation. 2004-11-09. accessed October 22, 2026.
5. Independent web analytics firm StatCounter confirms milestone as Chrome overtakes IE globally for first calendar month. StatCounter. 2012-06-01. accessed October 22, 2026.
6. Netscape Communications ships release 1.0 of Netscape Navigator and Netsite servers (press release posted to www-talk by Marc Andreessen). www-talk mailing list archive. 1994-12-15. accessed October 22, 2026.
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9. JavaScript: The First 20 Years (Allen Wirfs-Brock and Brendan Eich), Proc. ACM Program. Lang. 4, HOPL, Article 77. Association for Computing Machinery. 2020-06. accessed October 22, 2026.
10. DOJ's Request for New Court Order Shows that Internet Explorer is an Integrated Feature of Windows. Microsoft. 1997-12-23. accessed October 22, 2026.
11. U.S. v. Microsoft Corporation: Browser and Middleware (case page). U.S. Department of Justice, Antitrust Division. accessed October 22, 2026.
12. Judge: Microsoft is a Monopoly (Scott Bekker). Redmond Magazine. 1999-11-05. accessed October 22, 2026.
13. Microsoft Signs Consent Decree with U.S. Government to Settle Antitrust Case. Microsoft. 2001-11-02. accessed October 22, 2026.
14. Netscape Announces Plans to Make Next-Generation Communicator Source Code Available Free on the Net (press release, comp.os.os2.announce archive). MIT (Usenet archive). 1998-01-22. accessed October 22, 2026.
15. History of the Mozilla Project. Mozilla (www-archive.mozilla.org). accessed October 22, 2026.
16. History of the Mozilla Project. Mozilla. accessed October 22, 2026.
17. America Online Inc., Form 8-K (completion of the Netscape acquisition). U.S. Securities and Exchange Commission (EDGAR). 1999-03. accessed October 22, 2026.
18. FAQ. WHATWG. accessed October 22, 2026.
19. A fresh take on the browser (Sundar Pichai and Linus Upson). Official Google Blog. 2008-09-01. accessed October 22, 2026.
20. Commission Decision of 16 December 2009, Case COMP/C-3/39.530, Microsoft (tying). European Commission. 2009-12-16. accessed October 22, 2026.
21. Antitrust: Commission accepts Microsoft commitments to give users browser choice (IP/09/1941). European Commission. 2009-12-16. accessed October 22, 2026.
22. Antitrust: Commission fines Microsoft for non-compliance with browser choice commitments (IP/13/196). European Commission. 2013-03-06. accessed October 22, 2026.
23. New year, new browser: The new Microsoft Edge is out of preview and now available for download. Microsoft Windows Experience Blog. 2020-01-15. accessed October 22, 2026.
24. Internet Explorer 11 has retired and is officially out of support: what you need to know. Microsoft Windows Experience Blog. 2022-06-15. accessed October 22, 2026.
25. Browser Market Share Worldwide (September 2026). StatCounter Global Stats. 2026-09. accessed October 22, 2026.
26. Desktop Browser Market Share Worldwide (September 2026). StatCounter Global Stats. 2026-09. accessed October 22, 2026.
27. Browser Market Share United States of America (September 2026). StatCounter Global Stats. 2026-09. accessed October 22, 2026.
28. Desktop vs Mobile vs Tablet Market Share Worldwide (September 2026). StatCounter Global Stats. 2026-09. accessed October 22, 2026.
29. App Review Guidelines, guideline 2.5.6. Apple Developer. accessed October 22, 2026.
30. Department of Justice Wins Significant Remedies Against Google. U.S. Department of Justice. 2025-09-02. accessed October 22, 2026.
31. Court Issues Remedies Ruling in United States v. Google Search Case. Hughes Hubbard and Reed. 2025-09-03. accessed October 22, 2026.

Web Building Encyclopedia. First published October 22, 2026. Last reviewed October 22, 2026. Every fact on this page is linked to a source we opened. Spotted an error? Write to [email protected].