I just downloaded a very large text file with more than 70K lines of text, and had troubles loading it into a third party software getting an out of bounds error because of the size of the text file. The logical next step was to find a program to split the large text file into multiple smaller files, so that they could be loaded into the program separately afterwards.
Simple Text Splitter is an Open Source program for the Windows operating system, that can process large text files easily.

The portable program displays all options directly in the main interface on startup. To split a text file it needs to be loaded into the application by clicking on the Open Text button. Supported are all text based files, including txt, log or srt among others.
It may take a while before the text file has been loaded completely, depending largely on the size of the text file and the computer’s speed.
Several splitting options are listed on the right side. Here the number of chunks the text file will be split into can be selected, as well as the naming option for those files. The default naming convention is Partxx.txt, which can be changed to only numbers or Partxx and the original file name.
A click on the Start button starts the process, and splits the text file into the selected number of chunks.
Simple Text Splitter has been tested on a 64-bit Windows 7 Professional PC, it should work fine on most other Microsoft operating systems as well.
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The logical next step might be a program able to open the large text file.
Hi,
for splitting large text files, i use GSplit.
It’s very good.
http://www.gdgsoft.com/gsplit/
@ Niefer:
Hear, hear! ;)
to open a large text file get LTF (Large Text File) Viewer 5.2u
Thanks for this software. I was dividing my text file by hand, it was so difficult.
Hello,
I just tried your tool, but it can’t handle large files. I often end up with log files with 5+ million lines and just tried to open a 8 million line 1.2 gb file to split it in smaller pieces.
But thanks for trying.
Note: A tool that works for that kind of files is textcleaver http://bartdart.com/downloads/textcleaver.zip
Rock on! I’ve been looking for this for about an hour now but google turns up no valid results for “list splitter,” “split my big list,” etc. I was on the verge of swearing to it when I came across this. My file is only 2400 lines, needs to be split into sets of roughly 20 lines. I’ll try the one recommended in the post first, then look at the ones from the other commenters if it doesn’t work for me. MANY THANKS!