Creative Commons (CC) licenses have become a cornerstone of the free culture movement, enabling creators to share their work with the world while retaining certain rights. Whether you're a photographer uploading to Unsplash, Pexels, or Pixabay, a blogger searching for images, or a developer integrating open assets, understanding the nuances of CC licenses is essential. This article explains the six main Creative Commons licenses—from the most permissive (CC0) to the most restrictive (CC BY-NC-ND)—and helps you choose the right one for your needs.
What Are Creative Commons Licenses?
Creative Commons is a nonprofit organization founded in 2001 by Lawrence Lessig, Hal Abelson, and Eric Eldred. Its goal is to provide free, easy-to-use copyright licenses that allow creators to grant specific permissions to the public. Unlike traditional “all rights reserved” copyright, CC licenses follow a “some rights reserved” model. As of 2024, over 2.5 billion works worldwide use a Creative Commons license, according to the organization's own estimates.
All CC licenses share common features: they require attribution to the original creator (except CC0, which waives all rights), they are non-exclusive, and they are irrevocable. Each license is a combination of four conditions:
- BY – Attribution: Credit must be given to the creator.
- SA – ShareAlike: Adaptations must be licensed under identical terms.
- NC – NonCommercial: The work may not be used for commercial purposes.
- ND – NoDerivatives: No modifications or adaptations are allowed.
These conditions result in six main licenses, plus CC0 (Public Domain Dedication).
CC0 – The “No Rights Reserved” License
CC0 (Creative Commons Zero) is the most permissive option. It allows creators to waive all copyright and related rights, effectively dedicating their work to the public domain. Users can copy, modify, distribute, and use the work for any purpose—even commercial—without asking permission or providing attribution.
CC0 is popular among stock photo sites. For instance, Pexels and Pixabay use CC0 for most of their images. Unsplash originally used a custom license similar to CC0 but later adopted the Unsplash License, which is also very permissive. Many museums and cultural institutions also release digital reproductions of artworks under CC0, such as the Metropolitan Museum of Art in New York and the Rijksmuseum in Amsterdam.
While attribution is not legally required under CC0, it is considered good practice to credit the creator when possible. Some platforms, like Flickr, allow you to filter by CC0-licensed content.
CC BY – The “Attribution” License
CC BY is the most flexible license that still requires attribution. Users can share, adapt, and use the work commercially, provided they give appropriate credit to the original creator. This license is widely used by educational resources, such as Wikipedia (which uses CC BY-SA for text, but many images are CC BY), and by photographers on platforms like Flickr.
For example, if you use a CC BY photo in a blog post, you must include the creator's name, the title of the work, the license type, and a link to the original work. A typical attribution might read: “Photo by John Doe / CC BY.”
CC BY is recommended for creators who want maximum dissemination while still receiving credit. It is also the license used by Open Access journals like those published by PLOS.
CC BY-SA – The “ShareAlike” License
CC BY-SA adds a ShareAlike condition: any adaptations of the work must be licensed under the same or a compatible license. This is the license used by Wikipedia and many open-source projects. It ensures that derivative works remain free and open.
For instance, if you create a collage using CC BY-SA images, you must release the collage under CC BY-SA or a compatible license. This “copyleft” approach is similar to the GNU General Public License (GPL) for software.
CC BY-SA is ideal for collaborative projects where you want to encourage contributions while preventing proprietary reuse. However, it can be incompatible with other licenses, so careful mixing is required.
CC BY-NC – The “NonCommercial” License
CC BY-NC allows others to remix, adapt, and build upon the work for non-commercial purposes only. Commercial use is prohibited, though the definition of “non-commercial” can be ambiguous. According to Creative Commons, non-commercial means “not primarily intended for or directed towards commercial advantage or monetary compensation.”
This license is popular among artists and educators who want to share their work but restrict corporate use. For example, a photographer might release high-resolution images under CC BY-NC on their personal website, allowing bloggers and students to use them freely, but requiring companies to pay for a commercial license.
One downside is that CC BY-NC can limit the reach of the work, as many commercial entities may avoid it due to legal uncertainty. Also, if you use a CC BY-NC image in a video that later becomes monetized, you could be in violation.
CC BY-ND – The “NoDerivatives” License
CC BY-ND allows redistribution, commercial and non-commercial, but only in unmodified form. No adaptations, cropping, or editing is permitted. This license is often used by artists who want to protect the integrity of their work, such as photographers who don't want their images altered.
For example, if you download a CC BY-ND photo, you can share it on social media as-is, but you cannot crop it, add filters, or overlay text. You must also provide attribution.
CC BY-ND is less common in stock photography because many users need to edit images. However, it can be found on platforms like Flickr and some personal blogs.
CC BY-NC-SA and CC BY-NC-ND – The Most Restrictive
These two licenses combine NonCommercial with either ShareAlike or NoDerivatives.
- CC BY-NC-SA: NonCommercial and ShareAlike. Adaptations must be non-commercial and licensed under the same terms. Used by some educational resources and open courseware.
- CC BY-NC-ND: NonCommercial and NoDerivatives. The most restrictive license; users can only download and share the work as-is, for non-commercial purposes, with attribution. Often used by musicians on platforms like SoundCloud.
These licenses are suitable for creators who want to share their work for personal, non-commercial use while preventing modifications and commercial exploitation.
How to Choose the Right License
Selecting a Creative Commons license depends on your goals as a creator:
- Maximum dissemination – Choose CC0 or CC BY.
- Ensure derivatives remain open – Choose CC BY-SA.
- Prevent commercial use – Choose CC BY-NC or its variants.
- Protect work integrity – Choose CC BY-ND or CC BY-NC-ND.
For stock photographers, CC0 is common because it simplifies licensing for users. However, some photographers prefer CC BY to receive credit. If you're uploading to a platform like Unsplash, Pexels, or Pixabay, check their default license—most use CC0 or a similar permissive license.
If you're a user, always verify the license of any work you download. Many stock photo sites offer advanced search filters by license type. For example, Flickr's advanced search allows you to filter by “commercial use allowed” and “modifications allowed.”
Attribution Best Practices
When using CC-licensed works, proper attribution is crucial. Creative Commons recommends the TASL format: Title, Author, Source, License. For example:
“Mountain Sunset” by Jane Smith is licensed under CC BY 4.0. View the original at [link] and the license at [link].
If the work is CC0, attribution is not required but appreciated. For CC BY-NC-ND, you must include the attribution and cannot alter the work.
Some platforms generate attribution HTML automatically. For instance, Flickr provides a “Share” button that includes attribution code. Always double-check that the attribution is complete and accurate.
Where to Find CC-Licensed Content
Millions of CC-licensed works are available online. Popular sources include:
- Best Free Stock Photo Sites – Many use CC0.
- Free Stock Photo Licensing – A detailed guide.
- Flickr – Advanced search with CC filters.
- Wikimedia Commons – Mostly CC BY, CC BY-SA, or public domain.
- Europeana – Digital collections from European museums, many under CC0.
Always read the license terms carefully, as some works may have additional restrictions (e.g., model releases for people, trademark rights).
Conclusion
Creative Commons licenses empower creators to share their work on their own terms. Whether you're a photographer, writer, musician, or educator, there's a CC license that fits your needs. For users, understanding these licenses ensures you respect creators' rights while enjoying a vast pool of free content. Remember to always attribute properly, and when in doubt, choose the most permissive license to maximize your work's impact.
For a deeper dive into stock photo licensing, check out our Complete Guide to Stock Photos, AI Image Generation, and Licensing. If you're comparing platforms, see Unsplash vs Pexels vs Pixabay. For paid options, visit Top Paid Stock Photo Sites.