7zip Batch Zip

First, make sure that the 7zip directory is in your path. Usually, it is located at

C:\Program Files\7-Zip

Next, write the following in batch file

Zip all files in a directory

for /f %%A in ('dir /b') do 7z a -tbzip2 "%%A.bz2" "%%A"

Zip files with a specific extension in a directory (download batch file)

for /f %%A in ('dir /b *.txt *.dat') do 7z a -tbzip2 "%%A.bz2" "%%A"

Save and run in the directory where you want to zip the files.

Here, I am compressing using bzip2 (notice the switch: –tbzip2). You can change that to

-tzip for zip

-tgz for gz

-t7z for 7z

some more examples here.