To get the file sizes in KB:

Get-ChildItem | % {[int]($_.length / 1kb)}
Or to round up to the nearest KB:

Get-ChildItem | % {[math]::ceiling($_.length / 1kb)}
To get the number characters:

Get-ChildItem | % {(Get-Content $_.FullName).length}

credit to Dave Sexton from Stack Overflow