This can be automated with tools such as the Form Filler Extension for Google Chrome, but I prefer to key in data manually.
Why? Two reasons: 1) the data I fill in will be closer to production data [since I know what production data is like, unlike automated tools] and 2) to become more empathetic to the end users who will be using the page.
When keying in fake data, I could always use "123 First Street" for addresses, and "Joe Smith" for names, but I think it's a good idea to mix things up. Doing this can also reveal problems with how the page works (for example, a longer address might reveal that the the database field for storing address line 1 is too short).
To get a good variety of fictitious data, I use several sites.
fakenamegenerator.com. This one's a staple. It'll give you just about everything you need for a fictitious person. The one issue I've had with the site is that the product owners will think I'm testing with production data, since the fictitious identities are so convincing. On one occasion a product owner asked me to use an identity that's obviously fake (e.g. "Joe Sample"), because he was concerned that if a customer saw a screen capture of the page filled with with data from fakenamegenerator.com, they would think that we're divulging customer data!
randompassphrasegenerator.com. This site is useful for generating strong passwords that are easy to convey verbally and remember. Good when testing registration pages.
fillerati.com. This is nice for getting filler text. Uses some classic works of literature.
pdos.csail.mit.edu/archive/scigen. This is another site for generating filler text. The beauty of this site is that it generates random, nonsensical academic papers. You should read the story behind it -- it's quite amusing.
bing.com/gallery. A repository of high quality photographs. When I'm demoing or testing a page where users can upload images, I like using attractive images like these. Yes, it's Bing. You can make fun of me. Doesn't change the fact that the photographs are usually amazing.
frinkiac.com. I'm a big fan of classic Simpsons. This site lets you search for your favorite dialog from The Simpsons and download the images. Remember, no new crap. Seasons 2-20 only.
— Ben Osborne (@VisionsFugitive) August 12, 2016
generatedata.com. This is for when you want to generate a lot of data, most likely to import into your database. Like a bulk version of fakenamegenerator.com, but more customizable.
placehold.it. This is for creating placeholder images with specific dimensions.
The final link is my favorite. I also use it for creating filler text (yes, I'm a big advocate of quality filler text). The link is:
en.wikipedia.org/wiki/Special:Random
Now, if you're going to bookmark it (and I think you should), don't follow the link and bookmark the page you land on. You need to bookmark that URL, since you'll get redirected to a random Wikipedia page every time. It makes filler text fun and educational.
Want to take things to the next level? Here's what I did -- I created an AutohotKey script with a bunch of shortcuts to random WikiPedia articles. So I can key in "fil2" and AutoHotkey will replace it with an entire random article. If you have a meeting when you're demoing a page or pages where you have to fill in textareas, try this technique. For one thing it saves time, but you might also get a laugh or two.
Right now the WikiPedia articles are hard-coded in my AHK script, but I have an idea for a project where users can generate AHK scripts with keyboard shortcuts for n random articles. If/when I create that, I'll post the code here.
In the meantime, if you're a web developer, I hope you find something useful in my list.
