All of these websites offer free stock photos that can be used commercially, without attribution. Some of them have restrictions that do not allow redistribution, resale, print-on-demand, use in web templates for resale, and some other restrictions.
The reason for this list is so you don’t have to worry about attribution. Just comply with the terms as they are outlined by the site that is giving away the photos. As long as you do what they want and don’t use their photos for purposes they don’t agree with, you have nothing to worry about.
When in doubt as to whether your useage falls within what they consider acceptable, contact the site and ask before you use it. The worst they can do is say “no”, in which case you just go look for another photo with a more generous license.
Burst has photos released under a Creative Commons CC0 license, as well as under their own license. In both cases, you may use them for commercial purposes, without attribution. The photos under their own license can not be used to create a competing service.
Canva has a collection of free photos that you can download and use, commercially, without attribution. You will need to create a free account to be able to download them.
Free Stock Photos
Free Stock Photos has tons of photos with varying licenses, many of which allow for commercial use, including items meant for resale. Check the license terms included on the page with each photo.
FreeImages offers lots of high quality stock photos, free of charge, under a standard license that allows you to use them commercially, provided they are not being redistributed, used in web templates for resale, print-on-demand, or items where the photo is the main focus of the item. They were previously known as Stock.xchng, till their parent company was bought out by Getty. All of their commercial assets were then added to Getty’s collection. The old free photos site was then spun off as FreeImages.com.
Free Media Goo provides free images, audio files, textures and flash files that you can pretty much do whatever you please with them except use them in propaganda, pornography, or anything suggestive, according to their license.
Freerange Stock offers photos you can use for just about anything. They request that you give credit, but they also say it isn’t required if you don’t want to. There is a credit and link requirement if you use their photos as part of a web template, though.
freestocks.org has many photos you can use for commercial purposes, released under a Creative Commons CC0 license. While the license terms published on the site says they are all CC0, it also says you can’t sell the photos, themselves. But the CC0 license actually allows you to do just that. So, I’d be a little careful with this site, as they don’t seem to want to adhere to the letter of the license type they have chosen for their photos.
Gratisography claims to be the world’s quirkiest collection of free high-resolution pictures. I am not totally sure about that, but I am sure that they have a very generous license that allows you to do pretty much anything you want with their images, so long as it doesn’t involve redistribution of the image files or usage on merchandise where the image would be the main focus of the item.
Image*After lets you do anything you want with their photos, as long as you don’t use them to set up a stock photo site that competes with theirs.