Half-Life 2

Developer(s)

Valve Corporation

Publisher(s)

Sierra Entertainment (initial retail)
Electronic Arts (GotY edition)
Valve Corporation (digital)

Series

Half-Life series

Release date(s)

November 16, 2004

Windows:
November 16, 2004
Xbox:
November 15, 2005
Xbox 360:
October 10, 2007
PlayStation 3:
December 11, 2007
macOS:
May 26, 2010
Linux:
May 9, 2013
Android
May 12, 2014

Genre(s)

First-person shooter

Mode(s)

Single-player

Platform(s)

Windows, Xbox, Xbox 360, PlayStation 3, Android (Nvidia Shield), macOS, Linux

Engine

Source (Source 2013 SP)

Steam AppID

220

Written in

C++

Mod support

Yes (custom folder, sourcemods, Steam Workshop)

SDK

Source SDK

Documentation

Half-Life 2 level design

System requirements

Win Vista, 7 or later
1.7 GHz and/or Dual-core
1 GB RAM
6.5 GB disk space
NVIDIA GeForce 6xxx series, ATI Radeon X1600, Intel HD Graphics 3000
with 128 MB VRAM

New Engine only. For details, see below

Distribution

Retail, Steam

Official website

Links

Previous game

Next game

Half-Life 2: Lost Coast

Half-Life 2: Episode One (chronologically)

"Welcome. Welcome to City 17. You have chosen, or been chosen, to relocate to one of our finest remaining urban centers."

Half-Life 2 (abbreviated as HL2) defines a new benchmark in gaming with startling realism and responsiveness. Powered by then-new Source technology, Half-Life 2 features the most sophisticated in-game characters ever witnessed, advanced AI, stunning graphics and physical gameplay. This was the first game requiring installation of Steam when it came out back in 2004.

Half-Life 2 is the sequel to the 1998 Half-Life. A sequel to Half-Life 2 was released in 2006, titled Half-Life 2: Episode One, followed by Episode Two in 2007, being the last Half-Life 2 episode. A virtual reality prequel was released in 2020, titled Half-Life: Alyx.

Half-Life 2 was later ported for the Xbox console in 2005, as well as for the Xbox 360 and PlayStation 3 in 2007, bundled under The Orange Box. The console versions use Source 2007, and maps have been recompiled with HDR lighting data only.

A major update (Half-Life 2 20th Anniversary Update), has been released on November 16, 2024 to celebrate the 20th anniversary of the game. It adds Steam Workshop support, developer commentary, fixing various bugs, and both episodes (Episode One, Episode Two), aswell as Lost Coast now accessible directly on Half-Life 2 menu. There are also many other changes to the graphics, such as "Very High" shaders that enable Bicubic lightmap filtering, radial fog (enabled on some maps), and option to use classic fire/blood particle effect.^[1]

Note:Since November 16, 2024, any user who owns

Half-Life 2 (or any HL2 series game) can play:

Half-Life 2: Episode One

Half-Life 2: Episode Two

Half-Life 2: Lost Coast

Half-Life Deathmatch: Source

Half-Life 2: Deathmatch

Note:If you encounter issues (such as some textures rendered as white/black or completely transparent), or unable to use certain feature of a mod when playing a Source mod (example: MMod (FXAA anti-aliasing and some post-processing effects), Cinematic Mod, etc.) which mounts Half-Life 2 files, or installing a custom addon/mod (outside Steam Workshop) made prior to the update, you might need to downgrade the game to "steam_legacy - Pre-20th Anniversary Build", and/or wait for developers to make the game or mod compatible with changes after 20th Anniversary Update. This is because 20th anniversary update make changes to engine, shaders (such as adding bicubic lightmaps), and many other changes.

Features

This section only features changes exclusive to Half-Life 2 (and partially Half-Life: Source, Portal (since May 2025) or mods base directly on Half-Life 2 instead of SDK 2013), such as the recent 20th anniversary update. For features introduced in Source 2013 SP branch, see this page. For Source engine features, see Source engine page.

VGUI High DPI support (also in ): VGUI are now properly scalable on higher resolutions such as 4K (3840x2160).
Switch expansions through menu: Players can switch to Episode One and Two, aswell as Lost Coast through main menu. This feature works similar to Orange Box select game menu in Xbox 360 and PlayStation 3.
Bicubic lightmap filtering (also in ): Introduced in 2024, bicubic filtering is used on lightmaps when r_lightmap_bicubic is enabled, smoothing out aliasing caused by the lower resolution of lightmaps. It can be also enabled by setting the Shader detail to "Very High".
Radial fog (also in ): Unlike planar-based fog, radial fog does not strengthen or weaken the apparent amount of fog in a particular spot when you rotate the camera.; You can either use radial fog or planar-based fog by changing env_fog_controller "Use Radial Fog (fogRadial)" KeyValues.; Half-Life 2 only uses radial fog in certain maps, mostly large area such as Canals (in Water Hazard), or Coast (in Highway 17 and Sandtraps). Maps that use radial fog also have their fog value & distance changed.
Continue music playback after loading levels (also in ): Introduced in HL2's November 26, 2024 Update, music will continue to play after the next level is loaded, instead of stopping completely like in previous versions. Can be toggled using save_transition_music console command.

Content

Half-Life 2 content (hl2)
Half-Life 2: Episode One content (episodic)
Half-Life 2: Episode Two content (ep2)
Half-Life 2: Lost Coast content (lostcoast)
Half-Life 2 Complete (hl2_complete)
- On Steam, the game will be launched with hl2_complete, allowing users to switch to HL2, EP1, EP2 and Lost Coast through the menu (similar to The Orange Box on Xbox 360 & PlayStation 3). Running hl2.exe directly will instead launch hl2, with old UI font and without option for switching games through menu.
Source shared (hl2)
Source 2013 Singleplayer engine branch (updated version)

Other versions of Half-Life 2

Demo

Half-Life 2 has a demo version, available for free. The demo consists of excerpts of the Point Insertion and Ravenholm chapters (d1_trainstation_01 and d1_trainstation_02) and "We Don't Go To Ravenholm..." (d1_town_01, d1_town_02 and d1_town_03).

Note:If you already own the game, to enter the demo mode, use the -demo command line options.

Half-Life 2: Update

Main article: Half-Life 2: Update

Half-Life 2: Update is the mod developed by Fillip Victor, which improves Half-Life 2 by fixing bugs and featuring graphical improvements. It also includes Community Commentary, featuring Update developers and YouTubers (community).

This mod is no longer actively updated since 2015 and does not feature any new updates, bug fixes and features from Steam Deck update, Anniversary Update introduced in original Half-Life 2.

Half-Life 2 RTX

Main article: Half-Life 2 RTX

A ray-traced version of Half-Life 2 is currently under development by Orbifold Studios, and promoted by Nvidia, using Nvidia's RTX Remix tool. A demo version featuring only Ravenholm and Nova Prospekt was released in March 18, 2025.

This version aims to remaster the entire game with new ray-traced lighting, real-time reflections, PBR textures, and a lot more without changing the core gameplay, similar to Portal RTX.

Chapters

Half-Life 2 has 13 chapters (excluding Credits). In the demo version of the game, only two Point Insertion maps (d1_trainstation_01 and d1_trainstation_02) and "We Don't Go To Ravenholm..." (d1_town_01, d1_town_02 and d1_town_03) is playable.

Toggle chapters Half-Life 2 ChaptersToggle chapters
Point Insertion d1_trainstation_01	"A Red Letter Day" d1_trainstation_05	Route Kanal d1_canals_01	Water Hazard d1_canals_06
Black Mesa East d1_eli_01	"We Don't Go To Ravenholm..." d1_town_01	Highway 17 d2_coast_01	Sandtraps d2_coast_09
Nova Prospekt d2_prison_02	Entanglement d2_prison_06	Anticitizen One d3_c17_02	"Follow Freeman!" d3_c17_09
Our Benefactors d3_citadel_01	Dark Energy d3_breen_01

Since 20th Anniversary Update, users can switch to Episode One and Episode Two through Half-Life 2 menu, and play any Episodes chapters there. Lost Coast is also accessible through Extras main menu, with only one chapter named Lost Coast.

Half-Life 2: Episode One has 5 chapters (excluding Credits), and 7 chapters for Episode Two.

Toggle chapters Half-Life 2: Episode One ChaptersToggle chapters
Undue Alarm ep1_citadel_00	Direct Intervention ep1_citadel_03	Lowlife ep1_c17_00	Urban Flight ep1_c17_01
Exit 17 ep1_c17_05

Toggle chapters Half-Life 2: Episode Two ChaptersToggle chapters
To The White Forest ep2_outland_01	This Vortal Coil ep2_outland_02	Freeman Pontifex ep2_outland_05	Riding Shotgun ep2_outland_06a
Under the Radar ep2_outland_09	Our Mutual Fiend ep2_outland_11	T-Minus One ep2_outland_12a

NPCs

Main article: :Category:Half-Life 2 NPCs

Credits

Main article: Half-Life 2 Credits

Half-Life 2 Credits
These are the official credits for "Half-Life 2" as released in October 2004: Viktor Antonov Ted Backman Kelly Bailey Jeff Ballinger Matt Bamberger Aaron Barber Yahn Bernier Ken Birdwell Derrick Birum Chris Bokitch Steve Bond Matt Boone Charlie Brown Julie Caldwell Dario Casali Yvan Charpentier Jess Cliffe John Cook Greg Coomer Kellie Cosner Scott Dalton Kerry Davis Jason Deakins Ariel Diaz Quintin Doroquez Martha Draves Laura Dubuk Mike Dunkle Mike Dussault Rick Ellis Dhabih Eng Miles Estes Adrian Finol Bill Fletcher Moby Francke Pat Goodwin Chris Green Chris Grinstead John Guthrie Leslie Hall Damarcus Holbrook Tim Holt Brian Jacobson Erik Johnson Jakob Jungels Iikka Keranen Eric Kirchmer Marc Laidlaw Jeff Lane Tom Leonard Doug Lombardi Randy Lundeen Scott Lynch Ido Magal Gary McTaggart John Morello II Bryn Moslow Gabe Newell Tri Nguyen Jake Nicholson Martin Otten Kristen Perry Bay Raitt Alfred Reynolds Dave Riller Danika Rogers David Sawyer Aaron Seeler Nick Shaffner Taylor Sherman Eric Smith David Speyrer Jay Stelly Jeremy Stone Mikel Thompson Kelly Thornton Carl Uhlman Bill Van Buren KayLee Vogt Robin Walker Josh Weier Doug Wood Matt T. Wood Matt Wright Voices: Robert Guillaume - Dr. Eli Vance Robert Culp - Dr. Wallace Breen Lou Gossett, Jr. - Vortigaunt Michelle Forbes - Dr. Judith Mossman Merle Dandridge - Alyx Vance Mike Shapiro - Barney Calhoun Mike Shapiro - Gman Harry S. Robins - Dr. Isaac Kleiner Jim French - Father Grigori John Patrick Lowrie - Citizens\Misc. characters Mary Kae Irvin - Citizens\Misc. characters Ellen McLain - Overwatch Voice Casting: Shana Landsburg\Teri Fiddleman Voice Recording: Pure Audio, Seattle, WA LA Studios, LA, CA Voice recording scheduling and logistics: Pat Cockburn, Pure Audio Translations: SDL Crack Legal Team: Liam Lavery Jason Holtman Karl Quackenbush Kristen Boraas Kevin Rosenfield Alan Bruggeman Dennis Tessier Thanks to the following for the use of their faces: Jamil Mullen Art Min Larry 'The Count' Heard Ted Cohrt Roger Guay Frank Sheldon Travis Dunlop Daniel Dociu Van Crowder Joey Paresa Chau Luu Kim Harris-Jones Michael S. Smith Joe Cairo Naomi Cotton Sandro Consi Lakeetra Gilbert Erdin Grcic Kanisha Speyrer Warren Slough Special thanks to everyone at: Alienware ATI Dell Falcon Northwest Havok SOFTIMAGE and Don Kemmis, SLK Technologies

Limitations/Bugs

For more Half-Life 2 bugs, see this GitHub page.

This section only list various bugs that are commonly encountered.

☒ Unresolved bugs

None.

☑ Resolved bugs

Missing lighting on LDR / LDR with Bloom: Previous version of Half-Life 2 from 2010 to 2023 lacks LDR lighting on multiple game levels (starting from Black Mesa East (d1_eli_01) until the end of Nova Prospekt). This means that if HDR is disabled (by selecting "None" or "Bloom only" in HDR settings), mat_fullbright will be set to 1, disabling lighting and making everything bright and flat (relevant GitHub issue). Because of this, HDR is required to play the game until this is fixed.
This issue is not affected in the previous version of the game (which uses an older version of Source (Source 2004) and all of the maps lighting are compiled in LDR only), and is fixed in Half-Life 2: Update, aswell as 20th Anniversary update.

Dropship NPC gun broken: There was a bug with the Dropship's gun that was unable to turn, this makes the Sandtraps chapter much easier.^[2] This bug was introduced with Source 2007 engine branch and later, affecting both the console release of the game on X360/PS3 (remains unfixed) and later in 2010 with the Source 2009 engine update on Mac & PC release.
Fixed in the current Steam version since 2022's the Steam Deck update of Half-Life 2. However, there are many third-party Source mods (including Half-Life 2: Update, Synergy, etc...) which may or may not include this fix, plus the Source SDK Base 2013 code also does not include this fix by default; this page details how to fix it in your mod.

Other limitations

Important:The macOS (OS X) version of this game does not work on macOS Catalina (version 10.15) or later due to the removal of support for 32-bit-only apps.

As of May 26, 2010 (Mac), and later June 2010 on Windows, the branch of Source under which Half-Life 2 originally ran on Source 2006 no longer exists on Steam, and subsequently replaced by the updated Source 2009 (which later was upgraded again to Source 2013). Very old mods which base themselves directly on the game (as opposed to Source SDK Base) are unlikely to work any more.
This also meant that support for running Half-Life 2 on Windows 9x/ME/2000 have been also dropped.

The console port of the game for original Xbox, Xbox 360 and PlayStation 3 (on The Orange Box), no longer received any updates or bug fixes.

Technical notes

If Half-Life 2 was made to run on Source 2006 engine, this will cause performance drops when the train spawns in d1_canals_01. As Half-Life 2 was last updated in April 2006 and actually runs on Source 2004 until 2010, this bug is only present when players runs on Half-Life 2 on Source 2006 engine (either using pirated copies or by copying "hl2" folder to EP1 or Source SDK 2006). Some pirated copies of Half-Life 2 or Counter-Strike: Source (which ships with Half-Life 2 build 4044) also run on this version instead of build 2707.
- Also due to build 2733 and 4044 version of Half-Life 2 was actually a mod, and Half-Life 2 last Old Engine build was 2707 (Apr 6 2006), SourceRuns community (and speedrun.com) marked this build as illegitimate.
Although Source mods are often described as being "for Half-Life 2", they actually use the Source SDK Base. SDK Base is available to anyone who owns any Valve Source game and provides all of Half-Life 2's content (except maps and vcd scenes) on a static branch of the engine. However, this used to be the case before 2006, when Source SDK Base wasn't available.
The Half-Life 2 Collectors Edition, which ships with the 2004 version of the game, does not require Steam to run or update (similar to the latest version), which means that it will run on older systems with Windows 2000 and earlier. Since around 2010 or 2013, Half-Life 2 no longer requires Steam to run after installing it through Steam, but features such as Achievements will be unavailable.
The 64-bit Windows version of Half-Life 2 (and Lost Coast), which existed around 2005, is no longer available due to technical issues.

System Requirements

Windows (Old Engine):

OS: Windows 98 / ME, 2000, XP or later
CPU: 1.2 GHz
RAM: 256 MB
Disk space: 4.5 GB
Nvidia GeForce FX 5700, ATI Radeon 9500 (with 128MB VRAM)
Direct3D 9.0 compatible video card (with atleast DirectX 7.0 or higher feature level) and 128MB VRAM
Other: Steam required (except Collector's Edition copies)

Windows (New Engine):

OS: Vista, 7 or later
CPU:1.7 GHz and/or Dual-core
RAM:1GB RAM
Disk space: 15 GB
GPU (pre-20th): NVIDIA GeForce 6 series, ATI Radeon X1600, Intel HD Graphics 3000 (with 128MB VRAM)
GPU (post-20th): NVIDIA GeForce 200 series, ATI Radeon 4000 series, Intel HD Graphics 4000 (with 128MB VRAM)
Direct3D 9.0 compatible video card (with atleast DirectX 8.0 or higher feature level) and 128MB VRAM
Other: If you play the previous version of the game (from 2010 to 2023, or New Engine pre-20th anniversary) and run on DirectX 8.0 mode or having HDR disabled, the game will have issues with fullbright lighting due to Valve forgot to compile the maps with both LDR + HDR lighting. This issue has been fixed with 20th anniversary update. Also, if your game runs on DirectX 8 level by default, visit this page for fix.

Note:Original disk requirements are 6.5 GB prior to 20th Anniversary Update, which installs Half-Life 2: Lost Coast, Half-Life 2: Episode One and Half-Life 2: Episode Two content alongside Half-Life 2 and thus increase disk space requirements.

Additionally with 20th anniversary update, the highest settings will be more demanding to run on older hardware due to changes to 3D skybox in some maps (Sandtraps, d2_coast_10) aswell as LOD being disabled.

Note:Due to Steam dropping support on Windows XP/Vista, users need run the game without Steam by running the hl2.exe executable directly. Running the game without Steam will disable Achievements.

Note:The latest version is no longer compatible with Windows XP since the 2022 Steam Deck update. Earlier versions of Windows (98, ME, 2000) are also dropped.
User using Windows XP can downgrade to previous version of the game here. But please note that this version does not include all the bug fixes and new features that were introduced with Steam Deck and 20th Anniverasry Update.

Users with Collector's Edition copies (which runs on Source 2004, also supporting Win98/ME and 2000), or any Steam copies of Half-Life 2 since 2013 (SteamPipe), can play the game without Steam.

OS X:

OS X 10.5.8, 10.6.3 (up to 10.14.6)
CPU: 2.0 GHz and/or Dual-core
RAM: 1 GB
Storage: 15 GB
GPU: NVIDIA GeForce 8xxx series, ATI Radeon X1600, Intel HD Graphics 3000
OpenGL 2.1 compatible
Audio: OpenAL compatible
Other: HDR is required to be enabled (steam_legacy/previous branch only)

Note:Mac version are no longer supported after macOS Catalina (10.15), due to this game only have 32-bit binaries, meaning that Half-Life 2 will not work out of the box. Valve later removed macOS binaries in June 12, 2024.

User can manually build Intel 64-bit/Apple Silicon version of HL2 by following this guide. Additionally, the above 64-bit/Apple Silicon version currently does not work with 20th anniversary update yet.

Linux:

OS: Ubuntu 12.04, SteamOS 1.0 or later
Other Linux distros supported.
CPU: 2.0 GHz and/or Dual-core
RAM: 1 GB
Storage: 15 GB
GPU: NVIDIA GeForce 8xxx series, ATI Radeon X1600, Intel HD Graphics 3000
OpenGL 2.1 compatible
Audio: OpenAL compatible
Other: For steam_legacy/previous branch, HDR would be required.