Battle.net is an online game service, social network, digital store, and system for managing digital game rights created by Blizzard Entertainment. The service began on December 31, 1996. A few days later, on January 3, 1997, Blizzard released its action-role-playing game Diablo. In August 2017, the service was officially renamed "Blizzard Battle.net." This name was changed back to "Battle.net" in January 2021.

In March 2009, Blizzard introduced an updated version of Battle.net called Battle.net 2.0. More details about this update were shared at BlizzCon 2009, which highlighted support for games like World of Warcraft, StarCraft II, and Diablo III. The original version of Battle.net was later called Battle.net Classic. Games on Battle.net Classic use a different account system compared to games on Battle.net 2.0.

Today, Battle.net allows users to buy games, interact with others, and find matches for Blizzard’s modern PC games, such as Hearthstone, Heroes of the Storm, Overwatch 2, and StarCraft: Remastered. It also supports some Call of Duty games and Crash Bandicoot 4: It's About Time, which is developed by Activision, a company related to Blizzard. The platform lets players send messages and talk with friends across different games.

In September 2017, Blizzard released the Battle.net app for Android and iOS devices. The app allows users to chat with friends, add them as contacts, and see which games they are playing.

History

Battle.net was first introduced on December 31, 1996. The first game to use the service was Diablo, which released a few days later on January 3, 1997. At the start, Battle.net provided basic features like chat and game listings. Players could connect to the service, talk with others, and join multiplayer games of Diablo. Only user account information was stored on the servers, not any game data. When players joined a game, they connected directly to other players, not through Battle.net servers. This made the service fast and simple to use, but it also allowed cheating because players could change their game data locally. However, private games were available, so many players played with people they knew.

The release of StarCraft in 1998 greatly increased Battle.net’s use. Features like ladder rankings and game filters were added. After the release of StarCraft: Brood War, the number of players on Battle.net grew even more, with tens of thousands logged on at once, even today. StarCraft Battle.net was especially popular in South Korea, where the number of players was often much higher than in the United States.

StarCraft also introduced a new copy protection method using CD keys. Earlier, with Diablo, any player could connect to Battle.net. With StarCraft, only players with a valid CD key—a unique 13-digit number included with each boxed game—could access the service. Each CD key could only be used by one person at a time. CD keys could be muted (no chat), voided (limited to a specific channel), jailed (muted and voided), or banned entirely. Every Blizzard game after StarCraft used CD keys to connect to Battle.net. StarCraft: Brood War used the CD key from the original StarCraft on the same computer, so it could only be installed if the original game was already present. The Gateway system in Brood War allowed two players to play at the same time if they were on different gateways. Gateways operate separately, with their own game lists and user accounts, so players on different gateways could not join the same game or chat with each other.

Diablo II was released in 2000. A major change for Battle.net was the use of a client-server model. Instead of running on each player’s computer, the game was now managed by Blizzard’s servers. This meant all character data was stored on Battle.net servers. Diablo II also had an open character feature, allowing players to use characters locally or on a LAN and then play them on Battle.net. However, open games on Battle.net were not protected from cheating because players could still modify their characters locally. Another feature was the use of avatars in chat rooms that looked like players’ in-game characters. Diablo II also had a different Battle.net interface compared to earlier games, with expanded ladder support, including a "Hardcore" ladder where characters were permanently removed if they died in-game. Usage of Battle.net increased steadily, especially after the release of Diablo II: Lord of Destruction in 2001.

Warcraft III: Reign of Chaos was released in 2002, followed by its expansion, Warcraft III: The Frozen Throne, in 2003. These games added new features to Battle.net. The most significant was Anonymous Matchmaking, which let players press a button to be matched with others of similar skill levels. This made it easier to join games quickly and reduced win-trading, where players intentionally won or lost games to change their ladder rankings. Matchmaking was also expanded to team games through "Arranged Teams," where players could form teams with friends and be matched against other teams of the same size and skill level. However, some players found ways to cheat the system by intentionally losing games to make it easier for others to win. Automated tournaments were added in the expansion, where players competed to become tournament champions. Other features included chatroom icons based on wins, a friends list, and clan support.

In 2009, Blizzard Entertainment redesigned Battle.net. It was officially announced on March 20, 2009, and further explained at BlizzCon 2009. The new Battle.net had three sections. The first allowed players to combine all Battle.net accounts, World of Warcraft characters, and friends lists into a single account. Players could also unlock in-game achievements, which gave them avatars and decals visible on their profiles and in-game units.

The second section focused on making Battle.net a competitive platform. A new matchmaking system was introduced, making it easier for players to organize games. The ladder system was updated to group players by skill level, with leagues for different competitiveness levels. A practice league was added for training, where game speed was slower and maps were designed for a slower pace. The party system, similar to World of Warcraft, allowed friends to join games together.

The third section included a new chat system that allowed instant messaging across games, servers, and characters.

World of Warcraft initially had separate accounts from Battle.net until the 2009 redesign, which required players to merge their accounts. Features in World of Warcraft included cross-realm, cross-faction, and cross-game chat, letting players talk with friends on their Real ID list, other factions, servers, and games like StarCraft II and Diablo III. On November 11, 2009, Battle.net became a required feature for World of Warcraft players.

StarCraft II was the first game to support the redesigned Battle.net interface. It was released in three parts: the base game, "Wings of Liberty," and the expansion pack, "Heart of…"

Development

To help users protect their Battle.net accounts, Blizzard Entertainment added a two-step verification option for the service. In 2008, this was done using a separate device that users could buy from Blizzard. The device, which looked like a keychain, had special numbers linked to the user’s account. These numbers were used to confirm the user’s identity when logging into Battle.net. In 2009, Blizzard introduced the Battle.net mobile app for iOS and Android phones, which worked the same way. In June 2016, an update made the process easier. Users could now press a single button on their mobile device to confirm their identity when logging in from a computer. While two-step verification is not required to use Battle.net, some features in games require users to enable it through the device or app.

By November 1997, Blizzard said that Battle.net had 2.2 million games played, 1.25 million unique users, and added 3,500 new users each day. By April 1999, it was reported that Battle.net had 2.3 million active users and more than 50,000 users online at the same time. By September 2002, the number of active users reached 11 million. By September 2004, active users grew to nearly 12 million. At that time, users spent over 2.1 million hours online daily, with an average of 200,000 users online at once and a peak of 400,000 users online at the same time. In 2006, Blizzard said that Battle.net, combined with the World of Warcraft subscriber base, was a major leader in online gaming, noting that "even Xbox Live is not even close to us."

A group of developers has formed around Battle.net. Many unofficial programs for Battle.net are available, and most of the system used by Battle.net games has been studied and shared by volunteers.

Several tools for communication have been created, such as a "whisper" feature, which allows players to send private messages to friends during a game.

Custom games, which use maps not made by Blizzard Entertainment, have helped grow the community and now make up a large part of the games played. In Warcraft III, popular custom games include tower defense maps and "hero solo" maps (such as Defense of the Ancients and arena maps) or games like "Civilization Wars," where players build their economy, technology, and variety of units but do not directly control their units.

Controversy

A group of gamers studied the network protocol used by Battle.net and Blizzard games, then created a free software called bnetd that mimics the original system. This software allows players to use unofficial servers instead of the official Battle.net servers to play Blizzard games.

In February 2002, lawyers for Blizzard Entertainment threatened legal action under the Digital Millennium Copyright Act (DMCA) against the developers of bnetd. Blizzard games are designed to work only with servers controlled by Blizzard, known as "Battle.net." These servers check CD keys to prevent software piracy.

Even though the bnetd developers offered to include Blizzard’s CD key system in their software, Blizzard argued that any public software like bnetd could help pirates. Blizzard asked for the bnetd project to be shut down under DMCA rules. This case was one of the first major tests of the DMCA, so the Electronic Frontier Foundation became involved. Negotiations to resolve the case without a trial failed, and Blizzard won the case. The court ruled that the developers violated the End User License Agreement (EULA) for StarCraft and the Terms of Use for Battle.net. The decision was later upheld by the Eighth Circuit Court of Appeals in September 2005.

In July 2010, Blizzard announced a plan to require users to post their real names on their forums. The community strongly opposed the change, with many magazines calling it "foolhardy" and "Epic Fail." The change led to the largest user response in Blizzard’s history, including the sharing of personal details about a Blizzard employee who used his real name to show it was not a problem. Soon after, personal information about the employee, such as his phone number, picture, age, and home address, was posted online.

Some technology media suggested the real-name policy could help Battle.net and the community, but others worried it might put users at risk of real-life dangers like stalking or harassment. Concerns also included potential employment issues if employers searched for users’ online activity. Blizzard responded by saying the changes would not affect past posts, that parents could set up rules to prevent minors from posting, and that forum use was optional. Due to the strong negative reaction, Blizzard’s president canceled the plan temporarily.

In 2012, Blizzard faced several security issues. In May 2012, shortly after Diablo III launched, Blizzard discovered hacked accounts where players lost in-game items that could be sold for money. These accounts did not use Blizzard’s authentication system, and the company improved security by requiring authentication for the game’s Auction House. In August 2012, Blizzard reported that their Battle.net servers were hacked, and some user information, such as email addresses and scrambled passwords, was accessed. Blizzard did not confirm that accounts were compromised but asked users to change passwords and security questions.

These security problems led to a class-action lawsuit in November 2012, claiming Blizzard profited from selling Authenticator devices instead of improving server security and failed to inform users about the August data breach quickly. Most claims were dismissed in 2013 because the plaintiffs could not prove harm, and remaining claims were resolved through mediation. The case was closed in February 2014.

Games by Battle.net version

• Diablo
• Warcraft II: Battle.net Edition
• Diablo II (with Lord of Destruction expansion)
• StarCraft (with Brood War expansion)

• Diablo Shareware
• Diablo Spawn
• Diablo
• StarCraft Shareware
• StarCraft Spawn
• Japanese StarCraft (public beta of a Japanese version of StarCraft)
• Japanese StarCraft Spawn

• World of Warcraft (with The Burning Crusade, Wrath of the Lich King, Cataclysm, Mists of Pandaria, Warlords of Draenor, Legion, Battle for Azeroth, Shadowlands, and Dragonflight expansions)
• Warcraft III: Reforged
• StarCraft II: Wings of Liberty (with Heart of the Swarm and Legacy of the Void expansions)
• StarCraft: Remastered
• Diablo IV
• Diablo Immortal
• Diablo III (with Reaper of Souls expansion)
• Diablo II: Resurrected
• Hearthstone
• Heroes of the Storm
• Overwatch 2
• Blizzard Arcade Collection (including The Lost Vikings, Rock n' Roll Racing, Blackthorne, The Lost Vikings 2, and RPM Racing)
• Call of Duty: Black Ops 4
• Call of Duty: Modern Warfare (with Warzone)
• Call of Duty: Modern Warfare 2 Campaign Remastered
• Call of Duty: Black Ops Cold War
• Call of Duty: Vanguard
• Call of Duty: Modern Warfare II (with Warzone 2.0)
• Crash Bandicoot 4: It's About Time
• Call of Duty: Modern Warfare III
• Call of Duty: Black Ops 6
• Avowed
• Doom: The Dark Ages
• The Outer Worlds 2
• Sea of Thieves

• Overwatch
• Destiny 2
• Warcraft III: Reign of Chaos (with The Frozen Throne expansion)