-t (set Type of archive) switch

Specifies the type of archive.

Syntax

-t{archive_type}[:s{Size}][:r][:e][:a]
{archive_type}
Specifies the type of archive. It can be: *, #, 7z, xz, split, zip, gzip, bzip2, tar, ....
*:r
Default mode. 7-Zip opens archive and subfile, if it's supported by format.
*
Opens only one top level archive.
*:s{Size}[b | k | m | g]
Sets upper limit for start of archive position. Default scan size is 8 MBytes "*:s8m". Example: "*:s0" means that it will open only file that has no any stub before archive.
#
Opens file in Parser mode, and ignores full archives.
#:a
Same as *, but it opens files with unknown extensions that contain archives in Parser Mode.
#:e
Opens file in Parser mode and checks all byte positions as start of archive.

If -t{archive_type} switch is not specified, 7-Zip uses extension of archive filename to detect the type of archive. If you create new archive, -t{archive_type} switch is not specified and there is no extension of archive, 7-Zip will create .7z archive.

If -t{archive_type} switch is not specified and archive name contains incorrect extension, the program will show the warning.

It's possible to use the combined type (for example, mbr.vhd) for "Extract" and "List" commands for some archives.

When you extract archive of some types that contains another archive without compression (for example, MBR in VHD), 7-Zip can open both levels in one step. If you want to open/extract just top level archive, use -t* switch.

Note: xz, gzip and bzip2 formats support only one file per archive. If you want to compress more than one file to these formats, create a tar archive at first, and then compress it with your selected format.

Example

7z a -tzip archive.zip *.txt

adds all *.txt files from current directory to zip archive archive.zip.

7z t -t7z.split archive.7z.001

tests all files in archive.7z.001. It also checks that archive is multivolume .7z archive.

7z x -t# sfxarchive.exe

extracts sfxarchive.exe in parser mode.

7z x -tiso archive.iso

extracts files from archive.iso open as ISO archive.

7z x -tudf archive.iso

extracts files from archive.iso open as UDF archive.

Commands that can be used with this switch

a (Add), d (Delete), e (Extract), l (List), t (Test), u (Update), x (Extract with full paths)