The default wallpapers that come with your computer, phone, or tablet aren't necessarily terrible, but if you want to give your device a unique look, using a custom wallpaper is the best option. Here's how and where to find cool wallpapers online.
Google Image Search
Perhaps the easiest way to find a cool wallpaper that fits your liking is by just using Google Image Search. Start by typing in what you're looking for, followed by "wallpaper." Technically, you don't necessarily need to tack on "wallpaper" at the end of your search term, but it makes it a bit easier to narrow down images that are high resolution and the correct aspect ratio.
Even then, though, you might want to narrow things down further, especially if you have a QHD or 4K monitor. When you perform a Google Image Search for wallpapers, you'll find that 1920x1080 images dominate the results. You can be a bit more specific with your search and tack on extra keywords like "4K wallpaper" or "QHD wallpaper," but you'll get better results by using Google's advanced search tools
After performing your search, click the "Tools" option below the search bar.
In the tools that appear, click the "Size" option, point to the "Larger Than" menu, and then you can fine-tune the resolution shown in the search results.
You can also choose the "Exactly" option from the "Larger Than" menu and enter specific pixel dimensions to show only wallpapers with that exact resolution.
There are other tools you might want to explore as well. For example, if you click the "Color" tool, you can choose from options like full color; black and white; or even a specific focus color.
Here, for example, we've chosen the blue option from that menu and our search results all now favor blue as their primary color.
Of course, once you find the wallpaper you want in Google Image Search, you'll need to save it to your computer. Google has made that a bit more difficult recently by removing the old "View Image" button. You can bring back the "View Image" button with a Chrome extension, but if you don't use Chrome, you can simply right-click on the image and select "Save Image As" or something similar (depending on your operating system).
Other Wallpaper Sources
Aside from Google Image Search, there are a handful of dedicated wallpaper sites that you can browse to find something that you like.
Sites like DeviantArt, Papers.co, InterfaceLift, and Desktoppr offer dedicated wallpaper selections (or at least have a section offering wallpapers) that you can browse if Google Image Search isn't tickling your fancy. These are also places where a lot of independent artists post their work, so you can usually find something unique and exciting.
Make Your Own!
If you can't find anything that you like from various sources, don't be afraid to get your creative juices flowing!
If you're already familiar with Photoshop, you can either take existing images and modify them, or start from scratch and create something truly unique and one-of-a-kind.
But even if you don't know a lot about Photoshop (we have a great guide on how to learn, though), simply using a cool photo that you took with your phone can be good enough to use as a wallpaper for your device---no editing skills necessary.