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Compress most popular files in a glimpse of an eye.

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What Is Compress66?

Compress66 is a high-end online compression tool. Our free converter lets you easily compress your file to the desired size. You can either upload your file or drag and drop it into the blue box. Just select the file you want to compress and start the process.

What Are the Advantages of Data Compression?

Data compression has more advantages than most people realize. Storage space, such as that provided by memory cards or computer hard drives, comes at a price. Compressing your files allows you to store more data in the storage space you have available. Even if lossless compression is used, the target file size is typically 50 percent the size of the original file. Some formats, like .doc, can be compressed to 90 percent of their original size.

File compression is particularly useful for multimedia activities. As multimedia files tend to be very large, they often need to be reduced in size. Keep in mind that there are file types that often will not compress well (e.g. movie files in AVI or MPG format). Files that are already compressed, as these examples are, normally cannot be compressed more to any significant extent.

Because there is a sizable amount of reduction in the size of data to be transmitted, compressed files are much easier to transfer. Thanks to the quicker transmisson time, the file is available earlier. Especially when you need to send large files with hundreds of megabytes, you will appreciate the advantages of a professional compression tool like Compress66.

No Data Loss

Compress66 compresses your files in a glimpse of an eye. The great thing about our tool is that it reduces the file size without data loss. Choose a file, hit the „Compress“ button and see how the compression will be performed within seconds.

Unlike other compression tools, Compress66 provides lossless data compression. This means that every bit of data is retained when that information is compressed. Compress66 creates an identical version of the original data. This method is commonly used to compress data that can't tolerate loss of any kind. Examples might be log files or geometry formats.

Adjustable Quality

With, you can adjust the compression quality in order to get a perfect result. If you need to compress a file where the removal of some data bits has no visible effect on the representation of the content, lossy compression is very useful. In order to reduce or enhance the quality of the target file, drag the slider to set the desired quality level.

If you need to compress executables or spreadsheet files where the loss of words or numbers would change the information, we recommend choosing one of the higher quality levels. Graphics, on the other hand, can be either lossless or lossy. However, there are file formats that do not support lossless compression (e.g. standard JPG files).

Easy to Use – No Installation Required

Our compression tool does not need any special hardware in order to compress your files. The application is completely browser based and works with all operating systems (e.g. Windows, MacOS X, Linux). Just open the web page and start using the tool – it’s as simple as that.

As all files are compressed in the cloud (i.e. on our servers), the app does not consume your system resources. You do not need to download and/or install any software. Even with portable devices, you can compress files online and save or send them wherever you want. Please note that Compress66 does not support password protected archives.

Secure Online Compression

Compress66 is a highly secure online tool that is used by thousands of people per day. We do not keep your files longer than necessary on our server. All your original files and target files will be deleted after a short period of time (download links are valid 7 days by default). We do not store any personal information or give information to any third party. To learn more about this subject, please read our privacy policy.

Compressing Files with Compress66

Compress66 uses the standard upload feature of your browser. To add a file, just click on the blue box („Click here or drop file to start“). Now drag the slider to the desired quality level and click the „Compress“ button. Please note that the speed at which your file is uploaded is directly affected by the upload bandwidth available at the time the data is submitted.

If you are using the free version of our tool, you will see the following message: „Please wait 30 seconds in the queue to download your compressed file“. This message won't appear if you use the „Pro“ or „Ultimate“ version. The amount of time taken to process your file is related to the file size. Larger files will take longer to process. In most cases though, it shouldn't take longer than 30 seconds for the file to be processed.

Once your file has been compressed successfully, you have to enter a valid Email address. Solve the captcha and click on the "Send file to E-mail" button. The compressed file will be sent to your specified address. You have the option to share your compressed file on social networks (e.g. Facebook or Twitter). Just click one of the symbols to share your target file on the chosen platform.

Our Packages at A Glance

The basic functions of Compress66 are free to use for anyone. Our „Pro“ package ($5 per month) grants access to additional features. It comes free of ads and popups. Another advantage is that your files are stored for 30 days. In case of questions or problems, you receive priority support. Our „Ultimate“ package ($9 per month) gives you Pro access to all tools offered on (for example Apps66 and Apps66). All future tools are included.

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