filesize - How can I check the size of a file in a Windows batch script? - Stack Overflow

If the file name is not a parameter, you can do something like:

@echo off  setlocal  set file="test.cmd"  set maxbytesize=1000    FOR /F "usebackq" %%A IN ('%file%') DO set size=%%~zA    if %size% LSS %maxbytesize% (      echo.File is ^< %maxbytesize% bytes  ) ELSE (      echo.File is ^>= %maxbytesize% bytes  )

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