diff --git a/.github/workflows/rust-release.yml b/.github/workflows/rust-release.yml
index 2d137de6ff..5d6d3f7ca0 100644
--- a/.github/workflows/rust-release.yml
+++ b/.github/workflows/rust-release.yml
@@ -494,9 +494,10 @@ jobs:
             --package codex-responses-api-proxy \
             --package codex-sdk
 
-      - name: Stage macOS and Linux installer script
+      - name: Stage installer scripts
         run: |
           cp scripts/install/install.sh dist/install.sh
+          cp scripts/install/install.ps1 dist/install.ps1
 
       - name: Create GitHub Release
         uses: softprops/action-gh-release@v2
diff --git a/scripts/install/install.ps1 b/scripts/install/install.ps1
new file mode 100644
index 0000000000..40328db700
--- /dev/null
+++ b/scripts/install/install.ps1
@@ -0,0 +1,196 @@
+param(
+    [Parameter(Position=0)]
+    [string]$Version = "latest"
+)
+
+Set-StrictMode -Version Latest
+$ErrorActionPreference = "Stop"
+$ProgressPreference = "SilentlyContinue"
+
+function Write-Step {
+    param(
+        [string]$Message
+    )
+
+    Write-Host "==> $Message"
+}
+
+function Normalize-Version {
+    param(
+        [string]$RawVersion
+    )
+
+    if ([string]::IsNullOrWhiteSpace($RawVersion) -or $RawVersion -eq "latest") {
+        return "latest"
+    }
+
+    if ($RawVersion.StartsWith("rust-v")) {
+        return $RawVersion.Substring(6)
+    }
+
+    if ($RawVersion.StartsWith("v")) {
+        return $RawVersion.Substring(1)
+    }
+
+    return $RawVersion
+}
+
+function Get-ReleaseUrl {
+    param(
+        [string]$AssetName,
+        [string]$ResolvedVersion
+    )
+
+    return "https://github.com/openai/codex/releases/download/rust-v$ResolvedVersion/$AssetName"
+}
+
+function Path-Contains {
+    param(
+        [string]$PathValue,
+        [string]$Entry
+    )
+
+    if ([string]::IsNullOrWhiteSpace($PathValue)) {
+        return $false
+    }
+
+    $needle = $Entry.TrimEnd("\")
+    foreach ($segment in $PathValue.Split(";", [System.StringSplitOptions]::RemoveEmptyEntries)) {
+        if ($segment.TrimEnd("\") -ieq $needle) {
+            return $true
+        }
+    }
+
+    return $false
+}
+
+function Resolve-Version {
+    $normalizedVersion = Normalize-Version -RawVersion $Version
+    if ($normalizedVersion -ne "latest") {
+        return $normalizedVersion
+    }
+
+    $release = Invoke-RestMethod -Uri "https://api.github.com/repos/openai/codex/releases/latest"
+    if (-not $release.tag_name) {
+        Write-Error "Failed to resolve the latest Codex release version."
+        exit 1
+    }
+
+    return (Normalize-Version -RawVersion $release.tag_name)
+}
+
+if ($env:OS -ne "Windows_NT") {
+    Write-Error "install.ps1 supports Windows only. Use install.sh on macOS or Linux."
+    exit 1
+}
+
+if (-not [Environment]::Is64BitOperatingSystem) {
+    Write-Error "Codex requires a 64-bit version of Windows."
+    exit 1
+}
+
+$architecture = [System.Runtime.InteropServices.RuntimeInformation]::OSArchitecture
+$target = $null
+$platformLabel = $null
+$npmTag = $null
+switch ($architecture) {
+    "Arm64" {
+        $target = "aarch64-pc-windows-msvc"
+        $platformLabel = "Windows (ARM64)"
+        $npmTag = "win32-arm64"
+    }
+    "X64" {
+        $target = "x86_64-pc-windows-msvc"
+        $platformLabel = "Windows (x64)"
+        $npmTag = "win32-x64"
+    }
+    default {
+        Write-Error "Unsupported architecture: $architecture"
+        exit 1
+    }
+}
+
+if ([string]::IsNullOrWhiteSpace($env:CODEX_INSTALL_DIR)) {
+    $installDir = Join-Path $env:LOCALAPPDATA "Programs\OpenAI\Codex\bin"
+} else {
+    $installDir = $env:CODEX_INSTALL_DIR
+}
+
+$codexPath = Join-Path $installDir "codex.exe"
+$installMode = if (Test-Path $codexPath) { "Updating" } else { "Installing" }
+
+Write-Step "$installMode Codex CLI"
+Write-Step "Detected platform: $platformLabel"
+
+New-Item -ItemType Directory -Force -Path $installDir | Out-Null
+
+$resolvedVersion = Resolve-Version
+Write-Step "Resolved version: $resolvedVersion"
+$packageAsset = "codex-npm-$npmTag-$resolvedVersion.tgz"
+
+$tempDir = Join-Path ([System.IO.Path]::GetTempPath()) ("codex-install-" + [System.Guid]::NewGuid().ToString("N"))
+New-Item -ItemType Directory -Force -Path $tempDir | Out-Null
+
+try {
+    $archivePath = Join-Path $tempDir $packageAsset
+    $extractDir = Join-Path $tempDir "extract"
+    $url = Get-ReleaseUrl -AssetName $packageAsset -ResolvedVersion $resolvedVersion
+
+    Write-Step "Downloading Codex CLI"
+    Invoke-WebRequest -Uri $url -OutFile $archivePath
+
+    New-Item -ItemType Directory -Force -Path $extractDir | Out-Null
+    tar -xzf $archivePath -C $extractDir
+
+    $vendorRoot = Join-Path $extractDir "package/vendor/$target"
+    Write-Step "Installing to $installDir"
+    $copyMap = @{
+        "codex/codex.exe" = "codex.exe"
+        "codex/codex-command-runner.exe" = "codex-command-runner.exe"
+        "codex/codex-windows-sandbox-setup.exe" = "codex-windows-sandbox-setup.exe"
+        "path/rg.exe" = "rg.exe"
+    }
+
+    foreach ($relativeSource in $copyMap.Keys) {
+        $sourcePath = Join-Path $vendorRoot $relativeSource
+        $destinationPath = Join-Path $installDir $copyMap[$relativeSource]
+        Move-Item -Force $sourcePath $destinationPath
+    }
+} finally {
+    Remove-Item -Recurse -Force $tempDir -ErrorAction SilentlyContinue
+}
+
+$userPath = [Environment]::GetEnvironmentVariable("Path", "User")
+$pathNeedsNewShell = $false
+if (-not (Path-Contains -PathValue $userPath -Entry $installDir)) {
+    if ([string]::IsNullOrWhiteSpace($userPath)) {
+        $newUserPath = $installDir
+    } else {
+        $newUserPath = "$installDir;$userPath"
+    }
+
+    [Environment]::SetEnvironmentVariable("Path", $newUserPath, "User")
+    if (-not (Path-Contains -PathValue $env:Path -Entry $installDir)) {
+        if ([string]::IsNullOrWhiteSpace($env:Path)) {
+            $env:Path = $installDir
+        } else {
+            $env:Path = "$installDir;$env:Path"
+        }
+    }
+    Write-Step "PATH updated for future PowerShell sessions."
+    $pathNeedsNewShell = $true
+} elseif (Path-Contains -PathValue $env:Path -Entry $installDir) {
+    Write-Step "$installDir is already on PATH."
+} else {
+    Write-Step "PATH is already configured for future PowerShell sessions."
+    $pathNeedsNewShell = $true
+}
+
+if ($pathNeedsNewShell) {
+    Write-Step ('Run now: $env:Path = "{0};$env:Path"; codex' -f $installDir)
+    Write-Step "Or open a new PowerShell window and run: codex"
+} else {
+    Write-Step "Run: codex"
+}
+
+Write-Host "Codex CLI $resolvedVersion installed successfully."