Google On Image Filenames & A Surprising SEO Mistake

Google’s Lizzi Sassman and John Mueller discussed the importance of image filenames in a recent Search Off the Record podcast and at one point discussed a major mistake when it comes to filenames.

Importance of Filenames

Google’s documentation doesn’t say if image filenames are ranking factors.

But they do say that Google takes note of them in order to help figure out what the image is about.

For that reason it’s recommended by Google that images be given meaningful filenames.

Google’s image guidelines documentation states:

“Likewise, the filename can give Google clues about the subject matter of the image.

For example, my-new-black-kitten.jpg is better than IMG00023.JPG.

If you localize your images, make sure you translate the filenames, too.”

It’s also a good practice to give meaningful filenames to images because it makes it easier for organization purposes to be able to see the image filename and know what it’s about.

How Important Are Image Filenames?

Google’s Lizzi Sassman and John Mueller begin their discussion by affirming the importance of filenames then discuss how important they are in general.

“Lizzi Sassman:
So another part where you could focus your attention, I guess, would be the filename.

So words for the name of the image itself.

How important is that?

Because that’s not an area where I have not invested much effort, but I don’t know, like should we?

What if I went and just changed all of the images on our site to have a different filename?

To be more descriptive or, I don’t know… put like more words there too, like in addition to alt text?

John Mueller:
We do recommend doing something with the filenames in our image guidelines.

So having descriptive filenames is good.

But I don’t think you would see a significant change if you already do the other things around images, like the alt texts, the text surrounding the image.

Those are really, really strong signals.

And the filename itself is often… it’s kind of from a technical point of view.

This is what we called it, but it doesn’t provide any real unique information, usually.

Of course, if you don’t do the alt text, or if you don’t have good surrounding text, then, of course, the filename might be the only place where you mention what this image is about.

But if you do the rest, then usually the filenames are okay.”

Something to Know About Google Image Crawling

John Mueller next brings up an important technical issue regarding how Google crawls images and why this should be considered when optimizing images on an already established website.

John Mueller continued:

“And the other thing with filenames, especially for images, is when we crawl images, we tend not to crawl them as often, because usually, they don’t change a lot.

Lizzi Sassman:
Oh.

John Mueller:
So that means if you change all of the filenames across the website, then it’s going to take a lot of time for Google’s systems to see, “Oh, well, this is a new image, and we have to kind of look at it at some point.”

And to understand kind of that connection between the old image and the new one, that’s something that’s just going to take a very long time.

So if you changed all of them at once, my guess is… I don’t know, over a period of a couple of months at least, it’ll be kind of annoying in Image Search in that we kind of drop the old ones first because they’re no longer mentioned on the page and pick up the new ones in a really slow way.

So that’s something where I would try to only do that if it’s really, really critical.

Like when we did the transition from Blogger to the new set up for the blog posts.

Of course, the images had to be moved as well.

And at that point, it was like, “Sure.” It was like, “Change the filename, move the image to a different URL.” “

The big takeaway here is to be mindful that Google doesn’t crawl images very often and to be prepared to have renamed images not indexed for months.

Changing File Names Has Minimal Effect

Another important takeaway is that changing the filename of already crawled and indexed images has the least amount of benefit to the point that it wouldn’t be visible.

John Mueller continued:

“But otherwise, once they’re moved on the site, and you’re just like tweaking things, and it was like, “Oh, I have a new system for image filenames.”

I don’t think that would make it better.

That probably would have minimal effect, maybe no visible effect at all.

Lizzi Sassman:
For the amount of effort, yeah.

John Mueller:

And everything drops out for a couple of months. It’s no fun.

Lizzi Sassman:
And room for human error too. To like miss a broken link.

If you need to go swap out, where are these images embedded and stuff.

You could cause more problems with just a mistake of forgetting to update various places where those images were used.”

I can imagine things going wrong.”

Image Filenames and SEO

This segment of Google’s podcast had at least four insights on the topic of image filenames.

• Image filenames that are descriptive are helpful from an Image Search standpoint because they help Google understand what an image is about.
• Alt text and the text surrounding the image provide a stronger and more important signal about the image than the filename.
• Changing the image filename of an already indexed image has a “minimal effect” and likely won’t make it better.
• Changing the filename of an indexed image may result in the renamed image going uncrawled and not indexed for months.

Citation

Listen to the Search Off the Record Podcast

This segment can be heard at the 20:55 minute mark

Featured image by Shutterstock/Mix and Match Studio