Can we get the total size of data in GB that have not been modified in the last 5 years

Hi @john john Pter 

Thank you for posting your question in the Microsoft Q&A forum. 

SharePoint Online doesn’t provide a built‑in report that shows the total size of files that haven’t been modified for a long period of time. However, you can retrieve this information using either PnP PowerShell or Microsoft Graph, since every file exposes both its LastModifiedDateTime and Size. 

Below are two practical approaches: 

1.Use PnP PowerShell 

You can query your library, filter by last modified date, and sum the file sizes. 

Install-Module PnP.PowerShell 
Import-Module PnP.PowerShell 
  
# Connect to the SharePoint site 
Connect-PnPOnline -Url "https://yourtenant.sharepoint.com/sites/yoursite" -Interactive -ClientID <your application ID> 
  
# Cutoff date = today minus 5 years 
$cutoffDate = (Get-Date).AddYears(-5) 
$totalSize = 0 
  
$lists = Get-PnPList | Where-Object { $_.BaseType -eq "DocumentLibrary" -and $_.Hidden -eq $false } 
  
foreach ($list in $lists) { 
    $items = Get-PnPListItem -List $list.Title -PageSize 500 -Fields "FileRef","File_x0020_Size","Modified" 
  
    foreach ($item in $items) { 
        if ($item["Modified"] -lt $cutoffDate) { 
            $totalSize += [int]$item["File_x0020_Size"] 
        } 
    } 
} 
  
$totalSizeGB = [math]::Round($totalSize / 1GB, 2) 
Write-Host "Total size of files not modified in 5 years: $totalSizeGB GB" 

To connect PnP PowerShell, you may refer to How to connect to PnP Online with Interactive Authentication. 
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2.Use Microsoft Graph API 

GET /sites/{site-id}/drives/{drive-id}/root/children

 Graph also exposes file metadata, but you must enumerate everything yourself: 

-Recursively walk the entire drive (root > folders > subfolders > files). 

-For each file, compare lastModifiedDateTime with your 5‑year cutoff. 

-Add up the size values for all matching files. 

You’ll need to continue paging and drilling into folders until all items are processed. 

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