To split a large file into smaller junks, use something along the lines of: split -l60000 -d LargeFile.txt Prefix_Part_No_ This creates a new file every 60000 lines. Alternatively you can split by bytes: -b100m (every 100 MB) The following command will add a file extension .CSV to the split files: for file in * ; do mv $file `echo $file.CSV` ; done