List of Microsoft codenames

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I

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6 on 6

Windows Mobile 6.1.4

A

ADOS

OS/2 1.0

Advanced Windows

The original announced name for NT-based Windows, see Razzle

Alder

Windows CE 1.0

Anaconda

Xbox Series X

Andromeda

Canceled phone variant of Windows Core OS

Surface Pocket (cancelled Surface model designed to run Andromeda OS)

Another Fucking Driver

Ancilliary Function Driver (afd.sys)

Application Framework Extensions

Microsoft Foundation Class Library

Apollo

Windows Phone 8

Arcata

Surface Pro 9 (5G)

Argo

Zune

Asteroid

Windows 2000 Service Pack 1

Astro

MS-DOS 6

Canceled Lumia model, this model uses Qualcomm Snapdragon 820 (MSM8996) SoC.

Aurora

Windows Small Business Server 2011 Essentials

Avalon

Windows Presentation Foundation

B

Blackcomb

Planned successor of Windows XP and later Longhorn/Vista; named after Whistler Blackcomb, a ski resort in British Columbia popular among Microsoft executives

Birch

Windows CE 2.0

BirchWay

Surface Pro 9 (Intel)

BlackRock

Windows Dev Kit 2023

Blue

Windows 8.1

Bobcat

Windows Small Business Server 2003

Bobsled

Internal name for Windows Media Center Extender devices

Brooklin

Xbox Series X refresh, scheduled to be released in 2024

C

Cairo

Canceled successor of Windows NT 3.x that aimed to implement Bill Gates' "Information at your fingertips" vision

Cairo Domains

Active Directory

Cairo Messaging

Microsoft Exchange

CairOLE

OLE 3.0

Callaway

Windows Dev Kit 2023

Cambria

Surface Pro X (SQ1)

Carina

Surface Pro X (SQ2)

Cascades

Canceled successor to Windows Essential Business Server 2008 based on Windows Server 2008 R2.

Cascadia

Windows Terminal; also used as the name of the Cascadia Code and Mono typefaces, designed for the Terminal

Cassini

Windows Embedded 8

Caspar

Surface Pro X (Wi-Fi)

Cashmere

Word for Windows

Cedar

Windows CE 3.0

Centaurus

Surface Neo

Centro

Windows Essential Business Server 2008

Chelan

Windows Embedded Compact 7

Cherry Hill

Windows 11 shell experience pack updated via the Store

Chicago

Windows 95

Cityman

Lumia 950 XL

Cleveland

Alternative name for a canceled successor of Windows 95, more commonly known as Nashville

Cobalt

The 21H2 (second half of 2021) engineering semester of Windows as a service; the base for the original release of Windows 11

Colorado

Windows Small Business Server 2011

Control Program/DOS, CP/DOS

OS/2 1.0; follows IBM mainframe product naming

Copper

The late 2022 engineering milestone of Windows as a service

Cougar

The 32-bit DOS kernel in Windows 95 (DOS386.EXE/VMM32.VXD)

Windows Small Business Server 2008

Crossbow

Windows Mobile 6.0

Cruiser

OS/2 2.0

Cutter

OS/2 1.3

D

Darwin

Windows Installer

Daytona

Windows NT 3.5

Denali

Active Server Pages

SQL Server 2012

Deschutes

Windows 365 Cloud PC

Detroit

USB supplement update for Windows 95 OSR2

Diamond

Windows Media Center UI overhaul for Windows Vista

Dilithium

The early-2024 engineering milestone of Windows as a service. Named after the fictional material from Star Trek, as arsenic is infamous for its use in poisons.

DirectX Box

Xbox

Doesn't Matterhorn

Pre-reset Windows Vista

DOS 5.0

OS/2 1.0; name used primarily by Microsoft – implies that OS/2 is the successor to the multitasking MS-DOS 4.

Durango

Xbox One

E

Edmonton

Xbox One S

eHome

Windows Media Center

Eiger

Windows Fundamentals for Legacy PCs

Ellewood

Xbox Series S refresh, scheduled to be released in 2024

Elmer

Surface Laptop Studio 2

Elroy

Windows Live Mail

Emerald

Windows XP Media Center Edition 2005 Update Rollup 2

Epsilon

Surface Duo

Ersa

Surface Laptop Studio 2

Ethos

Surface Duo

Excalibur

SQ SoC

F

Fastbike

Fast boot in Windows Neptune (Profile Accelerated Boot Accelerator)

Freestyle

Windows XP Media Center Edition

Frosting

Microsoft Plus! Companion for Windows 95

Fiji

Windows Vista Media Center TV Pack

Firesteel

Internal Windows 11 self-hosting effort

Firebird

An upcoming update for Windows 10 Team

Football

OS/2 1.0–era multiple virtual DOS machines prototype using the virtual 8086 mode (previously known as Pigskin)

Fusion

Windows Side-by-Side Component Store (WinSxS)

.NET Framework CLR Loader

G

Galileo

Windows CE 3.0

Gallium

The mid-2023 engineering milestone of Windows as a service

Game SDK

DirectX

Gemstar

WebTV for Windows

GeorgeTown

Surface RT

GeorgeTown X

Surface Pro

Germanium

The late-2023 engineering milestone of Windows as a service; the base for the Windows 11 2024 Update

Guilin

Canceled Microsoft Lumia phone model. Utilized a Qualcomm Snapdragon 210 (MSM8909) SoC.

Gulliver

Surface Laptop Go 3

H

Haiku

Modular Windows

Harmony

Windows XP Media Center Edition 2004

Harvest

Surface Pro X (Wi-Fi)

Hobart

Surface Pro X (SQ1)

Honjo

Canceled Lumia model, this model uses Qualcomm Snapdragon 210 (MSM8909) SoC.

Hudson Valley

Rumored successor of Windows 11

Hydra

Windows NT Server 4.0, Terminal Server Edition

I

Idaho

Unrealized successor of Windows XP

Immersive Launcher, Immersive Shell

Start screen

Impala

Windows NT Embedded 4.0

Indigo

Windows Communication Foundation

Interface Manager

Windows 1.0

Iron

The 21H1 (first half of 2021) engineering semester of Windows as a service; the base for Windows Server 2022

J

Jaguar

The 16-bit MS-DOS subsystem in Windows 95. A standalone retail release was also planned at one point, which ultimately ended up not materializing

Jameson

Windows CE 4.1

Janus

Combined bundle of Windows 3.1 and MS-DOS 5

Canceled 64-bit port of Windows 2000 for Itanium-based systems

Jastro

Combined bundle of Windows 3.1 and MS-DOS 6; portmanteau of Janus and Astro

Jazz

Computer architecture based on the MIPS R4000 processor

Juneau

SQL Server 2012 Developer Tools

Jupiter

Windows CE 2.0

Windows Runtime

K

Kryptos

Xbox One

L

Linares

Surface Thunderbolt 4 Dock

Lite

Windows 10X

Lockhart

Xbox Series S

Lonestar

Windows XP Tablet PC Edition 2005

Longhorn

Windows Vista, Windows Server 2008; named after a bar situated between the Whistler and Blackcomb mountains.

M

Macallan

Windows CE 5.0

Magneto

Windows Mobile 5.0

Manganese

The 20H2 (second half of 2020) engineering semester of Windows as a service

Mango

Windows Phone 7.5

Mantis

Windows XP Embedded

Mars

Application framework used in Activity Centers, and the Help and Support Center in Windows Me and Windows XP

McKendric

Windows CE 4.2

Memphis

Windows 98

Merlin

Pocket PC 2002

Millennium

Windows Me

ModernPC

Windows 10X

MoGo

Start screen

Mojave

Fictitious release of Windows that was in fact rebranded Windows Vista, which was the subject of a Microsoft case study known as the Mojave Experiment

Monaco

Visual Studio Code; adopted as the name of the Monaco Editor, the code editor component of Visual Studio Code decoupled for use in other applications

Monad

PowerShell

Monarch

Outlook progressive web application

Monkton

Windows Dev Kit 2023

Monza

Surface Neo

N

Nashville

Internet Explorer 4; originally referred to a canceled successor of Windows 95.

Neptune

Canceled NT-based successor of the Windows 9x series; project merged with Odyssey in early 2000 to form Whistler. Sometimes stylized as NepTune.

NewShell

Shell Technology Preview; a series of updates for Windows NT 3.51 that backport the Windows 95 user interface

Nickel

The 2022 engineering milestone (also referred to as 22H2) of Windows as a service; the base for the Windows 11 2022 Update

NoDo

Windows Phone 7 March 2011 update

Northstar

Canceled Lumia model, this model uses Qualcomm Snapdragon 820 (MSM8996) SoC.

NT OS/2, NTOS

NT-based rewrite of OS/2 canceled in favor of Windows NT, see Razzle

NT Windows

Alternative name for Windows NT before that name was standardized, see Razzle

O

O'Hare

Internet Explorer 1; named after the international airport near Chicago, the codename for Windows 95.

Odyssey

Unrealized successor of Windows 2000; project merged with Neptune in early 2000 to form Whistler.

Omega-13

Longhorn development reset; named after the time travel device of the same name seen in Galaxy Quest's climax, which sends the user exactly thirteen seconds back into the past

One Outlook

Outlook progressive web application

Opus

Word for Windows

Orca

SNA Server 3.0

OS/2 3.0

NT-based rewrite of OS/2 canceled in favor of Windows NT, see Razzle

Ozone

Windows Mobile 2003

P

Panther

A short-lived lightweight fork of the Windows NT kernel for use in a consumer 32-bit version of Windows

WIM-based Windows Setup

Pegasus

Windows CE 1.0

Photon

Windows Phone 7

Pigskin

OS/2 1.0–era multiple virtual DOS machines prototype using the virtual 8086 mode (early name for Football)

OS/2 2.0 (early name for Cruiser)

Pinewood

Surface Pro X

Polaris

Canceled desktop variant of Windows Core OS

Portable OS/2

NT-based rewrite of OS/2, see Razzle

Porthole

Windows Libraries for OS/2

Portico

Windows Phone 8 GDR1

Protogon

ReFS

Q

Quatro

Windows Home Server

Quebec

Windows Embedded Standard 7

R

Rapier

Pocket PC 2000

Razzle

Windows NT 3.1; originally a rewrite of OS/2 based on the new NT kernel design, which was canceled with the IBM-Microsoft split in favor of Windows NT; kept as the name of the Windows NT build environment

Ren

Outlook; named after the fictional chihuahua cartoon character of the same name from The Ren & Stimpy Show

Redstone

Windows 10 Anniversary Update through October 2018 Update; named after the reactive mineral from Minecraft.

S

Saana

Lumia 650

Saimaa

Lumia 550

Salta

Surface Laptop SE

Santa Rosa

Surface Pro X (SQ2)

Santorini

Windows 10X

Scarlett

Xbox Series X/S

Scorpio

Xbox One X

Sebile

Xbox controller scheduled to be released in 2024

Shell Update Release

Windows NT 4.0

Sherlock

Dr. Watson

Sizzle

A collection of changes intended to improve overall OS/2 performance

Slate

Microsoft Management Console

Sloop

OS/2 1.2

Small Business Server "8"

Windows Server 2012 Essentials

Snowball

Windows for Workgroups 3.11

Solution Server

Windows MultiPoint Server 2010

Sparta

Windows for Workgroups 3.1

Spartan

Microsoft Edge

Sphinx

SQL Server 7.0

Spring '14, S14

Windows 8.1 Update 1

Stimpy

Windows 95 shell and user interface

Stimpy

Outlook; named after the fictional cat cartoon character of the same name from The Ren & Stimpy Show

Sundown

64-bit Windows NT (Win64); named as a jab at Sun Microsystems, as Solaris would be one of the main competitors in the 64-bit operating system market

Sun Valley

Windows 11

Suzuki

Surface Pocket (cancelled Surface model designed to run Andromeda OS)

Sydney

Bing Chat / Copilot

Symphony

Windows XP Media Center Edition 2005

T

Take Home

Windows Media Center internal dogfooding effort

Talisker

Windows CE 4.0

Talkman

Lumia 950

Tango

Windows Phone 7.5 July 2012 update

Tenjin

Surface Laptop SE

The Fucking Clown

Office Assistant

Titanium

Windows Mobile 6.5

Titanium

The 19H1 (first half of 2019) engineering semester of Windows as a service; the base for the Windows 10 May 2019 Update

Trimaran

OS/2 1.1

Triton

Planned minor update for Neptune

Tukwila

Unofficial codename for Windows NT 4.0 coined by Dave Cutler; named after a town in the neighborhood of Seattle to poke fun at Cairo

Threshold

Windows 10; named after an in-game location from Halo: Combat Evolved.

Tuva

Nano Server

U

Utopia

Microsoft Bob

V

Valo

Surface Pro 9 (5G)

Vanadium

The 19H2 (second half of 2019) engineering semester of Windows as a service; the base for the Windows 10 November 2019 Update

Vibranium

The 20H1 (first half of 2020) engineering semester of Windows as a service; the base for the Windows 10 May 2020 Update and later. Named after the fictional mineral from Marvel Comics to prevent confusion with the open source Chromium project

Vienna

Short-lived name for Blackcomb after a 2006 rename; the name was supposed to start a new set of codenames derived from popular cities and locations known for their "vistas".

Vail

Windows Home Server 2011

Viridian

Hyper-V

W

Whistler

Windows XP, Windows Server 2003; named after Whistler Blackcomb, a ski resort in British Columbia popular among Microsoft executives

Winball

Windows for Workgroups 3.1

Window Manager

Windows 1.0

Windows 7

Windows 7; coined by incrementing the version number of Windows Vista (6.0) by one

Windows 8

Windows 8

Windows NT 3.99

Internal effort to advocate for smaller and more easily achievable NT releases

Windows NT 5.0

Windows 2000; not a codename per se—according to a member of the development team, "Jim Allchin didn't like codenames."

Windows Presentation Foundation/Everywhere

Silverlight

WMS 2

Windows MultiPoint Server 2011

WMS 3

Windows MultiPoint Server 2012

Wolverine

TCP/IP-32 stack for Windows for Workgroups 3.11

Wren

Outlook; originated from Bill Gates mistaking Ren, the proper codename, for Christopher Wren, the architect of St. Paul's Cathedral.

X

Xenon

Xbox 360

Y

Yamazaki

Windows CE 6.0

Z

Zaca

Surface Pro 9 (Intel)

Zinc

The early 2023 engineering milestone of Windows as a service; the base for the Windows Server, version 23H2 and Azure Stack HCI, version 23H2