StockSnap.io

From the About us page:

Whether you're building a business website, creating a print brochure, crafting a digital or magazine ad, or some other brilliant creative project, you know that a great image helps your content transcend "good" and become "great." Compelling, eye-catching, attention-grabbing work on the web especially needs sharp, arresting visual images to succeed. That, in essence, is why StockSnap exists.