I find people asking me this question all the time lately. Image names, file names, do they really make a difference? Alt tags are important, obviously, but what about filenames?
Luckily, the answer to this question is easy. Yes they matter. That’s it. That’s the answer.
To be a little more precise, image names make a big difference in search engine optimization. If you don’t care about search engines then I guess you can stop reading right here. If you actually care about web traffic, though, search engines should make a huge difference.
One good way of seeing what the content on your page looks like to a web crawler is to use a program like LynxViewer. Lynx is a command-line based browser that is neat to use but not widely popular for many obvious reasons. My apologies if you are reading this on Lynx. Obviously you can’t view images in a command line (ASCII aside) and neither can the search engine crawlers.
They can, however, see image names and alt tags. Alt tags are best considered the same as content on the page. Don’t put anything in an alt tag that you wouldn’t want written as content, because that’s how it’s seen. Image names, though, are completely obscured to the user (unless they really want to find out, but honestly out of the thousands of images you see every day how many do you check?). This makes it awfully tempting to want to name it something useful for the developer. Popular examples are rightMenuAboutPage.gif or headTopWhiteCorner4.gif. Sometimes we use auto-generation programs to get image names and end up with 3459584711938.gif.
These filenames are hurting your optimization efforts. rightmenuaboutpage is not a word, much less a keyword you want to optimize for, but Google and other search engines give weight – arguably more than alt tags – to file names. In essence you are dilutingyour keyword pool with gibberish.
Okay so what do I do about it?
Another tempting methodology is to name your files better, but with underscores. white_elephant_ears.jpg tells me that you have a picture of a set of white elephant ears. It does not tell this to search engines.
I know, I just said that search engines give weight to filenames. That’s still true. The problem with the above elephant example is that it uses underscores. This is interpretted by a search engine as an actual character as opposed to a space. It’s the equivalent of putting ANY character there. You might as well use “t” instead of an underscore because it’s the same thing to a search engine crawler. whitetelephanttears.jpg.
The solution is to use dashes. It has been proven in the past (search around) that dashes do better than underscores when optimizing images for search engines. white-elephant-ears.jpg is the equivalent of telling google “white elephant ears”, which is presumably what you want. This technique will help you increase keyword density, add new relevant keywords, and increase search engine traffic (in theory).
Really, if you don’t have keywords, or some sort of descriptive word to use as a filename, you should get some. This won’t work as well without useful text in the filename. Still, a slightly irrelevant filename will do better than 458712937.jpg.
Ultimately a combination of useful filenames and descriptive keyword-oriented alt tags will go pretty far in increasing search engine ranks. I read a blog just this morning about a guy who increased his traffic threefold from search engines merely by optimizing his images. Obviously there’s no guarantee that you will see these same kind of results, but it will certainly be a step in the right direction.