Find-ModuleUpdate

Find-ModuleUpdate.ps1

# Faster to get them all at once than look up a few dozen individually
$galleryModules = Find-Module -Verbose:$false

# If you only want to update modules sourced from the PowerShell Gallery, you can add a filter by:
# Where-Object { $_.RepositorySourceLocation -eq "https://www.powershellgallery.com/api/v2/" }
Get-Module -ListAvailable -Verbose:$false | Group-Object Name | ForEach-Object {
    if (($_.Group | ForEach-Object Version | Select-Object -Unique | Measure-Object).Count -gt 1) {
        Write-Verbose "$($_.Name) has multiple versions installed, I will only check the highest version"
    }
    $module = $_.Group | Sort-Object Version -Descending | Select-Object -First 1 
    $galleryModule = $galleryModules | Where-Object { $module.Name -eq $_.Name }
    if (!$galleryModule) {
        Write-Verbose "Could not find module $($module.Name) in the PowerShell Gallery"
    } else {
        if ($galleryModule.Version -gt $module.Version) {
            "$($module.Name) by $($module.Author) @$($module.CompanyName) version $($module.Version) is outdated, $($galleryModule.Version) by $($galleryModule.Author) @$($galleryModule.CompanyName) is available"
        } else {
            Write-Verbose "$($module.Name) by $($module.Author) @$($module.CompanyName) version $($module.Version) is current"
        }
    }
}