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How to split and combine files in Windows? I need to split large files into several small sized files and then combine them after I transfer them to another box.

I'm fine with doing this on the command line.

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up vote 4 down vote accepted

I tend to compress the required file to a zip file, setting a maximum file size so that it gets split.

This means that you will always have the program to get the initial file back available.

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Addendum: 7-Zip can zip and split. Look for "Split to volumes, bytes", lower left corner when creating an archive in the GUI. – Nathaniel Dec 7 '09 at 22:33
it can split even without archiving, just like the rest. – Molly7244 Dec 8 '09 at 0:37
I tried this one. Very nice! The size of the package is about 1MG, less than GSplit (1.5MG). I need this tool to transfer files to a remote through a very slow connection. Therefore, the size of app is very important. – Dec 9 '09 at 22:54

Use HJSplit, it is simply the best.

HJSplit is freeware and portable (300 KB), and doesn't have to be installed.

There is an older free command-line version of Goetz's File Splitter, you may like this version if you plan on running batch scripts to split lots of files.

7-Zip is another free open source program that allows you split (with or without compression) and combine files, either via GUI (right click on the file > Split File... > choose size) or command line.

If you have Total Commander, it does that as well (Files > Split File...)

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Seconding Total Commander. – Gepard Dec 7 '09 at 21:48
Almost gave -1 vote for the horrible horrible color scheme – davr Dec 7 '09 at 22:19
hey, i'm just the messenger but i agree, it hurts the eyes :) other than that it's excellent and easy to use. – Molly7244 Dec 7 '09 at 22:26
Hey! Freebyte... good ol' Freebyte. – Nathaniel Dec 7 '09 at 22:32

For splitting files to exact sizes, you could always use the command line tool Linux / Unix tool: split. The windows version is here:

Using the tool you can split files to any size you would like, and you would use "cat" to recombine them.

For example:

split -b=10090000 bigfile.iso bigfile_part.

To split your files to exactly 10090000 bytes. Your output would look something like this:

bigfile_part.ab, etc.

To recombine just do:

cat bigfile_part* > bigfile.iso
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How do I split a stream. Trying to do this: some_long_running_data_process | split -l 10000 --name the_parts – Justin Thomas Nov 14 '15 at 14:46

If you just want to combine files (which have already been split somewhere else) you can do this in Windows Command Prompt natively:

copy /b example.ext.001+example.ext.002+example.ext.003+example.ext.004 example.ext

Just wanted to add that option.

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And it works great out of the box. :) – Achilles Dec 18 '14 at 21:42

I've been using this:

type file1 file2 file3 > out
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This only works for text files, and you are not adrressing how the OP can split the large files. – Jan Doggen Oct 28 '14 at 19:32
Did you test it before posting this claim? It actually works well for binary data as well. – Elmo Todurov Dec 3 '14 at 19:17
Elmo - your solution worked GREAT! Thanks a ton! I had a multi-part binary that I easily pieced back together using this. – paulburkeland Oct 19 '15 at 18:19

You can use WinRAR as a file splitter/joiner as well. To split a file into smaller files, select "Store" as the compression method and enter the desired value (bytes) into "Split to volumes" box. This way you can have split files named as filename.part1.rar, filename.part2.rar, etc.

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You might want to use GSplit. It's a powerful and free file splitter that lets you split your large files into a set of smaller files called pieces.

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+1 ... nice find. – Molly7244 Dec 8 '09 at 3:50

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