I created a Windows Powershell script file to fix issues with the Garmin Connect (Web) Weight Export function

#---- Start - ConvertGarminWeightCSV.ps1 ----------------------------------------------------------------------------------
# Login to https://connect.garmin.com/ & Navigate to 'Health Stats > Weight > 1 Year'
# at the top there is an export, that'll get you the csv.
# but the csv is in a poor format, with the date on the row above the data - this will reformat it for you
# also works with new format of multiple readings per day.
# Formatting includes removing the "lbs" and "%" signs in the numeric data fields and cleans any "--" data in those fields

#

#-----------------------------------
function Get-FileName($initialDirectory) {  
[System.Reflection.Assembly]::LoadWithPartialName("System.windows.forms") |     Out-Null

$OpenFileDialog = New-Object System.Windows.Forms.OpenFileDialog;
$OpenFileDialog.initialDirectory = $initialDirectory;
$OpenFileDialog.filter = "All files (*.*)| *.*";
$OpenFileDialog.ShowDialog() | Out-Null;
$OpenFileDialog.filename;
}

#-----------------------------------
Function Save-File ([string]$initialDirectory) {

    [System.Reflection.Assembly]::LoadWithPartialName("System.windows.forms") | Out-Null
    
    $OpenFileDialog = New-Object System.Windows.Forms.SaveFileDialog
    $OpenFileDialog.initialDirectory = $initialDirectory
    #$OpenFileDialog.filter = "CSV (*.csv)| *.csv"
    $OpenFileDialog.FileName = $SaveFileName
    $OpenFileDialog.ShowDialog() | Out-Null

    return $OpenFileDialog.filename

}
#-- Get Input and Output filename and locations ---------------------------------

$initialDirectory = "C:\Users\YOURNAME\Documents";

Write-Host "Please Select The File To Upload:";
$SourceFile = Get-FileName -initialDirectory $initialDirectory;
Write-Host "SourceFile: $($Sourcefile) ";
$SaveFileName = $sourceFile

Write-Host "Please Select The File To Save:";
$DestinationFile = Save-File
Write-Host "DestinationFile: $($Destinationfile) ";


#--- Read the CSV input file --------------------------------

# read the CSV input file in and add a Date column as first column
$csvin = import-csv $Sourcefile | Select-Object @{Name='Date';Expression={' '}},*

    #-- Start debugging ---------------------------------
    #Get the data in Table-like format
    #$csvin | Format-Table
    #$csvin | Out-Gridview
    #-- End debugging ---------------------------------
 
# Loop through each row in the CSV and
foreach ($row in $csvin) {
    # Check if the 'Name' column has a value
    if ($row.Time) {
        if ($row.Weight) {
            $row.Date = $datex
        } else {
            $datex = $row.Time.trim()

           
        }
    }
}



#--- Run through the input CSV, make format changes, drop the "date" records and prepare the output CSV file -----------------------
$deletedrows = 0
$outputrows = 0
$inputrows = 0

$csvout = foreach($row in $csvin) {
    $inputrows = $inputrows + 1
    #--- if this is a row with the time and all of the details then format it and keep it.
    if ($row.Weight) {
        $row.Weight = $row.Weight.SubString(0,$row.Weight.Length-4)
        if ($row.Change) {
            # remove " lbs" from end of string
            $row.Change = $row.Change.SubString(0,$row.Change.Length-4)
        }
        if ($row."Body Fat") {
            # remove " %" from end of string
            $row."Body Fat" = $row."Body Fat".SubString(0,$row."Body Fat".Length-2)
        }
        if ($row."Skeletal Muscle Mass") {
             if ($row."Skeletal Muscle Mass".trim().Length -eq 2) {
                # get rid of  the weird "--" in some fields that cause errors
                $row."Skeletal Muscle Mass" = " "
             } else {
                # remove " lbs" from end of string
                $row."Skeletal Muscle Mass" = $row."Skeletal Muscle Mass".SubString(0,$row."Skeletal Muscle Mass".Length-4)
             }
        }
        if ($row."Bone Mass") {
            if ($row."Bone Mass".trim().Length -eq 2){
                # get rid of  the weird "--" in some fields that cause errors
                $row."Bone Mass" = " "
            } else {
                # remove " lbs" from end of string
                $row."Bone Mass" = $row."Bone Mass".SubString(0,$row."Bone Mass".Length-4)
            }
        }
        if ($row."Body Water") {
            # remove " %" from end of string
            $row."Body Water" = $row."Body Water".SubString(0,$row."Body Water".Length-2)
        }
        #--- keep only the records with full details
        $row
        $outputrows = $outputrows + 1
    } else {
    #--- if this is NOT a row with the time and all of the details then delete it but keep count.
        $deletedrows = $deletedrows + 1
    }
}


Write-Host "Input Rows      : $($inputrows) ";
Write-Host "Deleted Rows  - : $($deletedrows) ";
Write-Host "                  ----- ";
Write-Host "Output Rows   = : $($outputrows) ";

    #-- Start debugging ---------------------------------
    #Get the data in Table-like format
    #$csvout | Format-Table
    #$csvout | Out-Gridview
    #-- End debugging ---------------------------------

#-- Output updated CSV file to selected location
 
$csvout | Export-Csv $DestinationFile -NoTypeInformation

#--- end

#---- End - ConvertGarminWeightCSV.ps1 ---------------------------------------------------------------------------------------------

Fix for converting to yyyy-mm-dd date.  Can't seem to edit/update post above (?)

    # Check if the 'Name' column has a value
    if ($row.Time) {
        if ($row.Weight) {
            $row.Date = $datex.ToString("yyyy/MM/dd")
        } else {
            $datex = Get-Date $row.Time.trim()
        }
    }