The short answer is yes, you can use Canva elements in your children's book that you create to sell on KDP or other publishing platforms that you sell for a profit. In this post, I'll explain why this is true.
First of all, there are two types of artwork available on Canva - free elements and pro elements. Each of these two types of elements have their own special terms.
Canva's Content License Agreement states that the free elements they offer either fall under the license of Pixabay, Pexels, or CC0, and if it doesn't fall under any of those, then it falls under Canva's own Free Content License Agreement.
If we jump over to the content license for Pixabay, we can see that Pixabay's terms allow users to use content for free, without having to attribute the author, and modify or adapt content into new works. When you create a children's book in Canva, and you're creating scenes by combining multiple elements, you are doing just that - adapting the content into new works. As long as you are creating a new and different design with the elements, you are able to use it for commercial use. For example, you couldn't just put a single image on a page and sell that - you need to combine things to make a new design that is all your own.
We can also look at the content license for Pexels. This basically has the same terms as Pixabay - free to use, attribution not required, and modify as you like. So again, as long as you are combining elements to create a new design, you are ok to use it for commercial use (i.e., to sell online).
Next, let's go over the terms for CC0 content. This is content that the creator has chosen to dedicate to the public domain by waiving their copyright rights to the work. You are free to use the work for any purpose.
Lastly, if the content does not fall under any of those categories, then it falls under Canva's own Free Content License Agreement, which states that Canva content maybe used on books and book covers, which is exactly what you'd be using it for in the case of creating a children's book.
First of all, there are two ways to acquire a license for a Pro Element. You can either have a free account, and pay for a Pro Element on a one-off basis (I believe it's usually $1 per element) or you can pay monthly/yearly for a Pro Account and have unlimited access to their Pro Elements.
Canva's terms state that "Each Pro Content License allows you to use the Content in one Canva Design, so you must pay to obtain a new license each time you wish to use the same piece of Content in a new Design". However, this shouldn't be a concern to you because Canva keeps track of this for you. When you have a free account, and you go to export the design, Canva will prompt you to pay for the Pro Elements before allowing you to download the high-res file.
If you have a Pro Account, then Canva will automatically issue you a new license every time you export a project, so you really don't have to think about it at all.
When you publish a book on KDP, you have the option to either check "I own the copyright and I hold necessary publishing rights" or "This is a public domain work". If you wrote your children's book and laid out the scenes in Canva, then you will check the first one, "I own the copyright and hold necessary publishing rights."
You do own the copyright to the work, because it is your own work of graphic design. You laid out the elements in your own unique way. You don't own the individual elements, but you DO own the way you uniquely put them together. That is your design and your work of art. You can read more about this at the Copyright.gov Visual Artist page.
You hold the necessary publishing rights, because you have the license from Canva (and/or Pixabay, Pexels, & Creative Commons) to include this work in your creation and to use it for commercial use.
Do I need to register my book with the copyright office?
The moment you create your work, it is yours, under the Artist's Copyright. So you do not need to register your work with the copyright office. If someone uses your work as their own, they are breaking the law and you can ask them to take it down. The main difference between having your work registered vs. relying only on the Artist's Copyright is that when it is registered, you can sue people for money if they made profits off your work. With the Artist's Copyright you can ask them to take it down, but they won't have to pay you any money.
You have to weigh the chances of this for yourself - is it worth it to pay to register your work? For me it is not, because the chances that someone is going to steal my work, AND make a sizable profit off of my work, is very slim. If I find that someone is using my work I'll just ask them to take it down and that is enough for me.
Does my book need a copyright page?
Your book does not need a copyright page, however it is a good practice because it is industry standard, and it provides some useful information about your book. It may also help to discourage people from stealing your content.
Do I need to credit Canva or Canva artists?
You do not need to give Canva or Canva artists credit for using their art in your designs. All of the licenses mentioned above - Pixabay, Pexels, CC0, and Canva's own license, state that attribution is not required.
Did I "illustrate" my book with Canva?
I also just wanted to clear up some terminology that I have been seeing going around. If you are using elements to create scenes for your book, you aren't illustrating your book, so make sure you don't use that terminology. You are only illustrating your book if you are physically drawing out the artwork. This can be traditionally using a pencil, pen, paint, or any other medium, or it can be done digitally on a Wacom Tablet, iPad, or other means. The point is, you are drawing the illustrations yourself.
If you are not drawing them and are instead using other people's illustrations to lay out scenes, then be careful of the words you use. If you say you illustrate it, that implies that you physically drew the artwork, and then you are taking credit for drawing something you didn't draw. Instead, you can say you designed the book, or you laid out the scenes.
A note about trademark
This isn't directly related to children's books, but I wanted to mention it anyways. Canva elements should not be used for trademarks. A trademark is an easily recognizable symbol, phrase, or word that denotes a specific product, for example, a logo. Canva's terms state, use any of the Content as part of a trade-mark, design-mark, trade-name, business name or service mark (excluding fonts).
Lastly, I'm not a lawyer
I'm not a lawyer, so please don't take this as official legal advice. If you need help with a legal issue, please contact an attorney.
Special thanks to Jonathan D'Silva, Director of the Penn State Intellectual Property Clinic, for his advice on this info! If you are in Pennsylvania and you have questions about intellectual property, you can reach out to the clinic for questions!
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