ZIP format features and performances
archiving format, mainstream on Microsoft Windows systems; ZIP file
specifications are maintained by PKWare which
originally developed the
Newer archive formats like 7Z and RAR have gained popularity and
introduced several improvements (some of them then brought into later
format revisions) as better compression ratio, recovery records to
rebuild accidentally missing data, strong
encryption etc, but ZIP format retained much of its popularity gained
in several years of widespread use, mainly for two factors:
Recently WinZip (probably the most popular zip file utility on MS
platform) introduced a new
encryption scheme, Advanced Encryption (AE), AES based; AE-encrypted
archives and classic
ZipCrypto-encrypted archives are supported by PeaZip (for legacy
compatibility purpose, ZipCrypto encryption is weak by today's
standards and should not be used for new files), and it is also
capable to read PKWare's AES encrypted zip archives.
- ZIP compression
is quite fast and it is
intensive (for today's standard) - it's based on Deflate algorithm
in GZip format), alternatively Deflate64 or BZip2 based compression is
possible, and supported by PeaZip - that makes ZIP format an ideal
candidate for archiving large quantities of mixed types of data (i.e.
performing a backup), when speed is more important than maximum
compression, which is usually the case with today's large disks and
large, poorly compressible multimedia files.
- ZIP support is nearly
distributions and Windows since XP have basic support for ZIP standard
out of the box), making ZIP format
the ideal choice when distributing files i.e. downloadable packages,
mail attachments etc.
Many archive/package formats (i.e. JAR, XPI, APK etc) are based on
modified ZIP standard, and can be consequently read by PeaZip.
Learn more about ZIP file format
ZIPX format features and performances
is a new
archiving format implemented in WinZip starting
12.1 release, evolved from ZIP specifications with newer data
compression algorithms - BZip, LZMA, PPMd and others.
It provides a compression ratio
comparable with RAR format, but ZIPX compression/extraction is
significantly slower than ZIP and marginally slower than RAR, in the
range of operating with 7Z
So, while ZIPX is a more feature-rich and powerful compression format
than ZIP, functionally it
is not an 1:1 replacement of it, being slower and not yet supported by
most third party utilities, an "issue" it shares with most of
ZIP alternative formats.
Learn more about ZIPX file format
TAR format features and performances
a pure-archiving format popular on Unix and Unix-like systems
used for backup and for content distribution on those platforms).
It does provide only archiving (concatenate input data and metadata in
a single output file), delegating functions as compression, encryption,
parity/integrity check, to external software working in pipeline with
TAR command output.
Learn more about TAR archives, GZIP compression, BZIP2
7Z format features and performances
open source archive
format, featuring AES encryption, native volume spanning, and high
compression ratio, in many cases (depending on the nature of the input
data), better than RAR and ZIPX formats.
The 7z archive format was introduced by 7-Zip
Windows platform and ported by p7zip
compression algorithms (LZMA/LZMA2, PPMd,
BZip2) can take benefit of
parallel computing on modern multicore CPUs, but 7Z is still a format
chosen when higher compression, and not speed, is the primary goal.
Learn more about 7Z file format
RAR format features and performances
proprietary archive format introduced by WinRar for
and ported to Linux (only as extractor) by the same Author, Eugene
RAR extraction routines were also rewritten as Open Source software
(PeaZip uses this Open Source RAR component from 7-Zip/p7zip project),
but its original license however does not allow third party to create a
RAR format advantages are better
compression ratio than ZIP, built-in strong
encryption, and error recovery capabilities with optional use of
For all those reasons, and being one of the first ZIP alternative
released, even being a proprietary format RAR is a very popular
choice especially for file distribution over the web, where the error
capability is a welcome advantage over most of other file formats.
Learn more about RAR file format
ACE format features and performances
proprietary archive format introduced on Windows platform by WinACE and
ported to Linux
as command line utility (extraction only) by the same Author of WinACE.
The format is currently less popular than in past years, it offers
improved compression compared to ZIP, but not as powerful as for RAR,
ZIPX, and 7Z formats.
Due to the commercial nature of the format no free software is
available for creating ACE archives, but UNACE for
extraction of ACE archives was made available as royalty free (for use
and distribution) closed source software.
PeaZip features UNACE for Windows and Linux as external plugin on
Add-ons page in order
to keep the base PeaZip package free of closed source software (only
software released under OSI approved licenses are included in the base
package) and provide end users the ability of unpacking ACE archives.
UNACE plugin for PeaZip is available either as installable package or
as compressed package to be installed by hand (recommended for PeaZip
portable), and it's free of charge.
Learn more about ACE file format
Other archival and compression formats properties
Lear more about CAB packages, and PEA file format.
ARC (or WRC) is a new, open source archiving
format developed by Bulat Ziganshin.
The format features
strong but speed/memory efficient compression, comparable to or better
than RAR an 7Z formats for most filetypes.
advantage of ARC
format is support for recovery records (like RAR), for
repair in case of corruption of the archive, and strong encryption with
AES, Serpent and Twofish
up to 256 bit key size) and Blowfish.
command line syntax is close to WinRAR one, allowing
easy porting of scripts from one program to the other.
PeaZip offers a GUI frontend to create, browse, test, repair and
extract ARC/WRC archives under Windows and Linux (on Gnome, KDE or
other desktop environments).
ARC/WRC files can be currently be browsed only in flat mode (shows all
objects in archive), but in any other aspect they can be handled as
ZIP/7Z files (see previous point).
Please note that ARC (or ARK) is also the extension of an archive
format developed by SEA company: it was of mainstream diffusion before
the introduction of ZIP, and it has
no connection with FreeARC's ARC format. PeaZip does not support SEA
LPAQ and most recent ZPAQ are
families of experimental compressors developed by
Matt Mahomey and contributors.
has very high
computational requirements (memory, CPU time) if compared to mainstream
compressors, but reaches
the highest compression ratio presently
possible. Most of top
ranking compression algorithms (i.e. Hutter prize winners)
belongs from PAQ family or
are derived works, as well as used in high compression utilities like
Archiver, WinUDA, WinRK and Emilcont. Best choice when maximum
compression is desired regardless speed and memory usage.
LPAQ is a
version of PAQ, meant to be faster but providing lower compression
levels; it is a compression only utility, so LPAQ-compressed files will
feature a double extension, i.e. filename.ext.lpaq. In PeaZip if
multiple files are sent to be compressed by LPAQ they will
be automatically added to a TAR archive before, resulting in the double
ZPAQ is the
evolution of the PAQ family, featuring backward
compatibility, while PAQ and LPAQ doesn't, so archives created with a
PAQ/LPAQ version need to be extracted with the same version. PeaZip
offers a GUI frontend to create, browse and extract many PAQ
(PAQ8F, JD, L and O) and LPAQ (LPAQ1 and LPAQ5) archive types, under
MS Windows and Linux (on Gnome, KDE or other desktop environments).
and BALZ are very efficient
compressor developed by Ilia Muraviev (QUAD and BALZ project pages),
high compression ratio and high extraction speed, due to the
observation most types of end users are expected to routinely unpack
data and rarely compress files.
QUAD and BALZ are single file compressors, so compressed files will
feature a double extension, i.e. filename.ext.quad.
In PeaZip, if multiple files are sent to be compressed by QUAD or BALZ
they will be automatically added to a TAR archive before, resulting in
the double extension TAR.QUAD or TAR.BALZ respectively. PeaZip offers a
GUI frontend to create, browse and extract QUAD and
BALZ compressed files, under Microsoft Windows and Linux (on Gnome, KDE
(speed, best compression ratio) of archive file formats in
mainstream archive manager utilities see PeaZip's compression benchmarks
Read more on Wikipedia
page about comparison
of archive formats in terms
of features and reciprocal advantages / disadvantages.
Useful online resources: PKWare (creators
ZIP format), WinZip, 7-Zip, WinRAR, PAQ Wikipedia
entry, ZPAQ project