What is the file extension Popularity rating and how is it determined?

Each file extension entry in FileInfo.com includes a Popularity rating that defines how popular the file extension is.

The Popularity rating is based on a scale from 1 to 5. The ranking scores are defined as follows:

	Rare	File extensions that are no longer used or are only used by obscure programs are given a "Rare" rating. Most users will never see file types with these extensions.
	Uncommon	File extensions used by programs that not very popular are given an "Uncommon" rating. These file types are often referenced by programs and are not seen by the user.
	Average	File extensions that are used by most programs are given an "Average" rating. The average user will come across several of these file types, but not on a regular basis.
	Common	File extensions that are used by popular programs are given a "Common" rating. These file types are typically saved by popular programs and are useful to know.
	Very Common	File extensions that are used by the most common programs are given a "Very Common" ranking. These file types are ubiquitous and are seen by many users on a daily basis.

You can use the Popularity rating to determine how common various file extensions are. For example, it may be helpful to remember the file associations of extensions with "Common" and "Very Common" ratings. To view a list of file extensions that have a "Very Common" ranking, visit the Common File Extensions page.

The Popularity rating is also a good indicator of how easy it will be to find a program to open the associated file type. This is because file extensions with higher Popularity ratings are typically associated with more prevalent software programs. For file extensions with multiple file associations, the Popularity rating can help you determine what the most likely file type is.

Since new software programs are frequently introduced, file extensions can change in popularity. Therefore, while the file extension Popularity ratings typically remain consistent, you may notice some ratings occassionally change. If you see an extension with a Popularity rating that you feel should be changed, please submit your request and FileInfo.com will take it into consideration.