diff --git a/backend/README.md b/backend/README.md
index 31be561b56..06f71e24d6 100644
--- a/backend/README.md
+++ b/backend/README.md
@@ -115,6 +115,22 @@ This README provides a quick setup guide for the Omi backend. For a comprehensiv
     deactivate
     ```
 
+## Running Backend Test Preflight
+
+Before running the full backend test suite, use the preflight script for your shell. It checks the Python test runner, key packages, optional service environment variables, Redis reachability, and `test.sh` file references.
+
+macOS/Linux:
+```bash
+bash test-preflight.sh
+```
+
+Windows PowerShell:
+```powershell
+powershell -NoProfile -ExecutionPolicy Bypass -File .\test-preflight.ps1
+```
+
+The preflight script does not replace `test.sh`; it only catches setup issues before running the tests.
+
 ## Additional Resources
 
 - [Full Backend Setup Documentation](https://docs.omi.me/developer/backend/Backend_Setup)
diff --git a/backend/test-preflight.ps1 b/backend/test-preflight.ps1
new file mode 100644
index 0000000000..53dd69bcb5
--- /dev/null
+++ b/backend/test-preflight.ps1
@@ -0,0 +1,202 @@
+param()
+
+$ErrorActionPreference = "Continue"
+
+$RootDir = Split-Path -Parent $MyInvocation.MyCommand.Path
+Push-Location $RootDir
+
+$PassCount = 0
+$WarnCount = 0
+$FailCount = 0
+$Script:PythonLauncher = $null
+
+function Add-Pass {
+    param([string]$Message)
+    Write-Host "  OK    $Message" -ForegroundColor Green
+    $script:PassCount += 1
+}
+
+function Add-Warn {
+    param([string]$Message)
+    Write-Host "  WARN  $Message" -ForegroundColor Yellow
+    $script:WarnCount += 1
+}
+
+function Add-Fail {
+    param([string]$Message)
+    Write-Host "  FAIL  $Message" -ForegroundColor Red
+    $script:FailCount += 1
+}
+
+function Invoke-SelectedPython {
+    param([string[]]$Arguments)
+    if ($Script:PythonLauncher -eq "py") {
+        & py -3 @Arguments
+    } else {
+        & $Script:PythonLauncher @Arguments
+    }
+}
+
+try {
+
+Write-Host "Tools:"
+
+$pythonCommand = Get-Command python -ErrorAction SilentlyContinue
+if ($pythonCommand) {
+    $Script:PythonLauncher = $pythonCommand.Source
+    $pythonVersion = (& $Script:PythonLauncher --version 2>&1)
+    Add-Pass "python $pythonVersion"
+} elseif (Get-Command py -ErrorAction SilentlyContinue) {
+    $Script:PythonLauncher = "py"
+    $pythonVersion = (& py -3 --version 2>&1)
+    Add-Pass "python $pythonVersion"
+} else {
+    Add-Fail "python not found"
+}
+
+if ($Script:PythonLauncher) {
+    $pytestOutput = Invoke-SelectedPython @("-m", "pytest", "--version") 2>$null
+    if ($LASTEXITCODE -eq 0) {
+        Add-Pass $pytestOutput
+    } else {
+        Add-Fail "pytest not installed (pip install pytest)"
+    }
+} else {
+    Add-Fail "pytest not checked because python is missing"
+}
+
+if (Get-Command black -ErrorAction SilentlyContinue) {
+    Add-Pass "black (formatter)"
+} else {
+    Add-Warn "black not installed - pre-commit hook will fail (pip install black)"
+}
+
+Write-Host ""
+Write-Host "Python packages:"
+
+$missingPackages = @()
+foreach ($pkg in @("pydantic", "fastapi", "firebase_admin", "google.cloud.firestore", "redis", "deepgram_sdk", "openpipe")) {
+    if (-not $Script:PythonLauncher) {
+        $missingPackages += $pkg
+        Add-Warn "$pkg not checked because python is missing"
+        continue
+    }
+
+    Invoke-SelectedPython @("-c", "import $pkg") *> $null
+    if ($LASTEXITCODE -eq 0) {
+        Add-Pass $pkg
+    } else {
+        $missingPackages += $pkg
+        Add-Warn "$pkg not importable"
+    }
+}
+
+if ($missingPackages.Count -gt 0) {
+    Write-Host "  -> Run: pip install -r requirements.txt" -ForegroundColor Yellow
+}
+
+Write-Host ""
+Write-Host "Env vars (unit tests):"
+
+if ($env:ENCRYPTION_SECRET) {
+    Add-Pass "ENCRYPTION_SECRET (set in env)"
+} else {
+    Add-Pass "ENCRYPTION_SECRET (set by test.sh - no action needed)"
+}
+
+Write-Host ""
+Write-Host "Env vars (integration - optional):"
+
+function Test-OptionalEnv {
+    param(
+        [string]$Name,
+        [string]$Description
+    )
+    if ([Environment]::GetEnvironmentVariable($Name)) {
+        Add-Pass "$Name ($Description)"
+    } else {
+        Add-Warn "$Name not set ($Description)"
+    }
+}
+
+Test-OptionalEnv "OPENAI_API_KEY" "LLM calls - some integration tests skip without it"
+Test-OptionalEnv "DEEPGRAM_API_KEY" "STT streaming and pre-recorded transcription"
+Test-OptionalEnv "ADMIN_KEY" "admin endpoint tests"
+Test-OptionalEnv "REDIS_DB_HOST" "Redis connection (default: localhost)"
+Test-OptionalEnv "REDIS_DB_PASSWORD" "Redis auth"
+Test-OptionalEnv "GOOGLE_APPLICATION_CREDENTIALS" "Firebase/Firestore integration tests"
+
+Write-Host ""
+Write-Host "Services:"
+
+$redisCli = Get-Command redis-cli -ErrorAction SilentlyContinue
+if ($redisCli) {
+    $redisHost = if ($env:REDIS_DB_HOST) { $env:REDIS_DB_HOST } else { "localhost" }
+    $redisPort = if ($env:REDIS_DB_PORT) { $env:REDIS_DB_PORT } else { "6379" }
+    $redisArgs = @("-h", $redisHost, "-p", $redisPort)
+    if ($env:REDIS_DB_PASSWORD) {
+        $redisArgs += @("-a", $env:REDIS_DB_PASSWORD)
+    }
+    $redisArgs += "ping"
+
+    & $redisCli.Source @redisArgs *> $null
+    if ($LASTEXITCODE -eq 0) {
+        Add-Pass "Redis ($redisHost`:$redisPort) - connected"
+    } else {
+        Add-Warn "Redis ($redisHost`:$redisPort) - not reachable (integration tests may fail)"
+    }
+} else {
+    Add-Warn "redis-cli not installed - cannot check Redis connectivity"
+}
+
+Write-Host ""
+Write-Host "Test files:"
+
+$unitTests = @(Get-ChildItem -Path "tests/unit" -Filter "test_*.py" -Recurse -ErrorAction SilentlyContinue)
+if ($unitTests.Count -gt 0) {
+    Add-Pass "$($unitTests.Count) unit test files found"
+} else {
+    Add-Fail "No unit test files found in tests/unit/"
+}
+
+$missingTests = @()
+if (Test-Path "test.sh") {
+    foreach ($line in Get-Content "test.sh") {
+        if ($line -match '^pytest\s+(tests/\S+)') {
+            $testFile = $Matches[1]
+            if (-not (Test-Path $testFile)) {
+                $missingTests += $testFile
+            }
+        }
+    }
+
+    if ($missingTests.Count -gt 0) {
+        Add-Fail "test.sh references missing files: $($missingTests -join ', ')"
+    } else {
+        Add-Pass "All test.sh references resolve to existing files"
+    }
+} else {
+    Add-Fail "test.sh not found"
+}
+
+Write-Host ""
+Write-Host "Summary:"
+$total = $PassCount + $WarnCount + $FailCount
+Write-Host "  $PassCount passed  $WarnCount warnings  $FailCount failed  ($total checks)"
+
+if ($FailCount -gt 0) {
+    Write-Host "  Fix failures above before running test.sh" -ForegroundColor Red
+    exit 1
+}
+
+if ($WarnCount -gt 0) {
+    Write-Host "  Warnings are optional - unit tests should still pass" -ForegroundColor Yellow
+    exit 0
+}
+
+Write-Host "  All clear - ready to run test.sh" -ForegroundColor Green
+exit 0
+
+} finally {
+    Pop-Location
+}