We arrived at this estimate using Google's cache (see files below) in conjunction with the statistics for each platform we're aware of that:
- includes at least one million works under a CC license, CC0, or the Public Domain Mark, and
- is not included in Google's cache.
Those platforms are as follows:
| Platform name | Number of works (rounded down by millions) | source |
|---|---|---|
| Flickr | 307 million | https://www.flickr.com/creativecommons/ |
| Wikipedia (all pages in all languages) | 111 million | http://meta.wikimedia.org/wiki/List_of_Wikipedias |
| Scribd | 50 million | Source at Scribd |
| MusicBrainz | 39 million | https://musicbrainz.org/statistics |
| Freebase | 39 million | https://developers.google.com/freebase/faq#how_big_is_freebase |
| deviantART | 15 million | https://creativecommons.org/weblog/entry/35540 |
| Geonames | 10 million | http://www.geonames.org/about.html |
| YouTube | 10 million | Source at YouTube |
- Current CC tools (295 million)
- Retired CC tools (6 million)
For the sake of simplicity and precision, this data includes only Google's cache; therefore, it doesn't include the platforms listed above.
We created the geographical breakdown of licensors' locations using the web statistics for our License Chooser page. The Chooser is available in 34 languages and is prominently featured on CC affiliate websites worldwide; therefore, its visitors are more geographically diverse than those of the creativecommons.org homepage, which primarily offers content in English.
That said, people who use the chooser represent only a fraction of all CC licensors. Since creativecommons.org is more popular in English-speaking countries than in non-English-speaking countries, these numbers are weighted toward the United States and other English-speaking countries.
This data reflects the time span of January 1 to September 30, 2014.
Google found 9 million websites (defined as any web domain) with a link to a current or retired CC license deed.
A national commitment is defined as any national legislation or government-mandated project that leads to the creation, increased use, or improvement of open educational resources by requiring an open license. Descriptions of each of the 14 policies are available in the OER Policy Registry.
Nicole Allen of SPARC developed this estimate by surveying each of the open textbook programs that SPARC tracks and finding out how many students were impacted, and the price of comparable traditionally-published textbooks. See Nicole's presentation.
Thanks to the following organizations, companies, and individuals for their contributions to this report.
- deviantART: Josh Wattles
- Google: Henry Lien, Matt McLernon, Fred Von Lohmann
- Microsoft
- Tom Rubin
- Scribd: Jared Friedman
- SPARC: Nicole Allen
- Everyone who donates to Creative Commons