Article relating to File Compression Software Review

File Compression Software Compression Test

TopTenREVIEWS File Compression Software Review Article

By Erin Monaghan

Methodology
ZIP is the most common and widely-used compression format today. To test for each file compression program’s compression capabilities, we created ZIP archives using each of the file archivers in our review. We chose to compress a series of file types that are commonly used by the average computer user. We used the maximum compression option available in each program.

We then listed the compression ratio for each file type rounded to the nearest percent and added the results for an overall compression ratio.

Although all of the software we reviewed could write ZIP archives, some of the file compression software was not originally designed to support ZIP as its main archive type. In these cases, we used the software to compress to a ZIP archive and also the native archive of program.

Admittedly, this is a small scale test to demonstrate ratios in a controlled environment. Compression may vary with larger files and folders with mixed extensions.

*Please Note*- WinZip, our #1 product, offers two popular compression options, “Legacy” and “Best.” “Best” is WinZip’s maximum compression option, but “Legacy” is more compatible with older versions of WinZip and therefore, more likely to be used.

Materials
We compressed five different but commonly used file types including:

Photos- JPEG
PDF
Music MP3
Word DOC
Excel XLS

Photos- Our photo file consisted of 30 images in JPEG format. Images were an average of 106KB each.

PDFs- We compressed two PDF files, each more than 1MB.

Music- Our music file consisted of 12 songs from one album. Songs were previously ripped to our hard drive and compressed at 128kbps.

Word documents- We compressed 15 Word documents, each with about 500 words.

Excel spreadsheets- The Excel folder consisted of 10 spreadsheets varying in size from 47KB to 413KB.

ZIP Test Results:

	JPEG	PDF	MP3	DOC(X)	XLS(X)	Total Compression
WinZip (best)	16%	11%	1%	87%	88%	203%
Quick Zip	6%	10%	2%	85%	82%	185%
TurboZip Express	4%	10%	2%	86%	83%	185%
7-Zip	4%	10%	2%	86%	83%	185%
WinRAR	4%	10%	2%	86%	82%	184%
IZArc	4%	10%	2%	85%	82%	183%
TUGZip	4%	10%	2%	85%	82%	183%
BitZipper	4%	10%	2%	85%	82%	183%
StuffIt	4%	10%	1%	85%	83%	183%
WinZip (legacy)	4%	10%	1%	85%	82%	182%
WinAce	4%	10%	1%	84%	80%	179%

The results of our ZIP test indicated that with the exception of the WinZip “Best” compression, there is only a 6% difference between products with the best ZIP compression and those with the worst.

Also, document files consistently had better compression, whereas files that were considered to already have some compression, including photographs and music, the file compression software did little to save space. WinZip “Best” is the exception, performing almost 4 times better than almost all the other programs in the JPEG category.

Other Archives Test

	JPEG	PDF	MP3	DOC(X)	XLS(X)	Total Compression
STIX (StuffIt)	21%	11%	13%	93%	86%	224%
7Z (7-Zip)	4%	11%	2%	93%	92%	202%
RAR (WinRAR)	4%	11%	2%	86%	85%	188%
ACE (WinACE)	4%	11%	2%	91%	80%	188%
ALZ (ALZip)	4%	10%	2%	70%	80%	166%

I the chart above, you can see that while StuffIt didn’t perform particularly well in the ZIP test, their in-house SITX is a compression powerhouse showing significant compression with JPEG and MP3 files, files that were already compressed in some way prior to using the archiver.

Alternatively, the ALZip format ALZ had more difficulty compressing documents and spreadsheets in its native archive compared to a ZIP archive.

Conclusion

Our compression test demonstrated that with the exception of WinZip’s new “Best” compression option, there is very little difference in ZIP compression ratios, no matter which software performs the task. The best compression ratio is in text based documents including Word files and Excel spreadsheets. However, the alternative archive formats test shows that many other formats have better compression than the popular ZIP archive.