Moz Q&A is closed.
After more than 13 years, and tens of thousands of questions, Moz Q&A closed on 12th December 2024. Whilst we’re not completely removing the content - many posts will still be possible to view - we have locked both new posts and new replies. More details here.
How important is the file extension in the URL for images?
-
I know that descriptive image file names are important for SEO. But how important is it to include .png, .jpg, .gif (or whatever file extension) in the url path? i.e. https://example.com/images/golden-retriever vs. https://example.com/images/golden-retriever.jpg
Furthermore, since you can set the filename in the Content-Disposition response header, is there any need to include the descriptive filename in the URL path?
Since I'm pulling most of our images from a database, it'd be much simpler to not care about simulating a filename, and just reference an image id in my templates.
Example:
1. Browser requests GET /images/123456
2. Server responds with image setting both Content-Disposition, and Link (canonical) headersContent-Disposition: inline; filename="golden-retriever"
Link: <https: 123456="" example.com="" images="">; rel="canonical"</https:> -
In theory, there should be no difference - the canonical header should mean that Google treats the inclusion of /images/123456 as exactly the same as including /images/golden-retriever.
It is slightly messier so I think that if it was easy, I'd go down the route of only ever using the /golden-retriever version - but if that's difficult, this is theoretically the same so should be fine.
-
@Will Thank you so much for this response. Very helpful.
"If you can't always refer to the image by its keyword-rich filename"...
If I'm already including the canonical link header on the image, and am able to serve from both /images/123456 and /images/golden-retriever (canonical), is there any benefit to referencing the canonical over the other in my image tags?
-
Hi James. I've responded with what I believe is a correct answer to MarathonRunner's question. There are a few inaccuracies in your responses to this thread - as pointed out by others below - please can you target your future responses to areas where you are confident that you are correct and helpful? Many thanks.
-
@MarathonRunner - you are correct in your inline responses - it's totally valid to serve an image (or other filetype) without an extension, with its type identified by the Content-Type. Sorry that you've had a less-than-helpful experience here so far.
To answer your original questions:
- From an SEO perspective, there is no need that I know of for your images to have a file extension - the content type should be fine
- However - I have no reason to think that a filename in the Content-Disposition header will be recognised as a ranking signal - what you are describing is a rare use-case and I haven't seen any evidence that it would be recognised by the search engines as being the "real" filename
If you can't always refer to the image by its keyword-rich filename, then could you:
- Serve it as you propose (though without the Content-Disposition filename)
- Serve a rel="canonical" link to a keyword-rich filename (https://example.com/images/golden-retriever in your example)
- Also serve the image on that URL
This only helps if you are able to serve the image on the /images/golden-retriever path, but need to have it available at /images/123456 for inclusion in your own HTML templates.
I hope that helps.
-
If you really did your research you would have noticed the header image is not using an extension.
-
Again, you're mistaken. The Content-Type response header tells the browser what type of file the resource is (mime type). This is _completely different _from the file extension in URL paths.
In fact, on the web all the file extensions are faked through the URL path. For example, this page's URL path is:
https://a-moz.groupbuyseo.org/community/q/how-important-is-the-file-extension-in-the-url-for-images
It's not
https://a-moz.groupbuyseo.org/community/q/how-important-is-the-file-extension-in-the-url-for-images.html
How does the browser know the the page is an html doc? Because of the Content-Type response header. The faked "extension" in the URL path, is unnecessary.
You can view http response headers for any URL using this tool.
-
-
Do you need a new keyboard?
-
@James Wolff: I'm really hoping you're being sarcastic here. As it's totally fine to serve it without the extension. There are many more ways for a crawler to understand what type a file is. Including what @MarathonRunner is talking about here.
-
This isn't accurate. File extension (in the url path) is not the same as the **Content-Type **response header. Browsers respect the response header Content-Type over whatever extension I use in the path.
Example: try serving a file /golden-retriever.png with a content type of image/jpeg. Your browser will understand the file as a .jpg. If you attempt to save, your browser will correct to golden-retriever.jpg.
You can route URLs however you want.
Additionally, I'm not aware of any way browsers "leverage cache by content type". Browsers handle cache by the etag/expires header.
Browse Questions
Explore more categories
-
Moz Tools
Chat with the community about the Moz tools.
-
SEO Tactics
Discuss the SEO process with fellow marketers
-
Community
Discuss industry events, jobs, and news!
-
Digital Marketing
Chat about tactics outside of SEO
-
Research & Trends
Dive into research and trends in the search industry.
-
Support
Connect on product support and feature requests.
Related Questions
-
Google Image Search - Is there a way to influence the related icons at the top of the image search results?
Google recently added related icons at the top of the image search results page. Some of the icons may be unrelated to the search. Are there any best practices to influence what is positioned in the related image icons section? Thank you.
Intermediate & Advanced SEO | | JaredBroussard1 -
Removing Toxic Back Links Targeting Obscure URL or Image
There are 2 or 3 URLs and one image file that dozens of toxic domains are linking to on our website. Some of these pages have hundreds of links from 4-5 domains. Rather than disavowing these links, would it make sense to simply break these links, change the URL that the link to and not create a redirect? It seems like this would be a sure fire way to get rid of these links. Any downside to this approach? Thanks,
Intermediate & Advanced SEO | | Kingalan1
Alan1 -
Underscores, capitals, non ASCII characters in image URLs - does it matter?
I see this strangely formatted image URLs on websites time and again - is this an issue - I imagine it isn't best practice but does it make any difference to SEO? Thanks in advance, Luke
Intermediate & Advanced SEO | | McTaggart0 -
Faceted Navigation URLs Best Practices
Hi, We are developing new Products Pages with faceted filters. You can see it here: https://www.viatrading.com/wholesale-products/ We have a feature allowing to Order By and Group By, which alters the order of all products. There will also be the option to view Products as a table, which will contain same products but with different design and maybe slightly different content of each product. All this will happen without changing the URL, https://www.viatrading.com/all/ Is this the best practice? Thanks,
Intermediate & Advanced SEO | | viatrading10 -
Does rewriting a URL affect the page authority?
Hi all, I recently optimized an overview page for a car rental website. Because the page didn’t rank very well, I rewrote the URL, putting the exact keyword combination in it. Then I asked Google to re-crawl the URL through Search Console. This afternoon, I checked Open Site Explorer and saw that the Page Authority had decreased to 1, while the subpages still have an authority of about 18-20. Hence my question: is rewriting a URL a bad idea for SEO? Thank you,
Intermediate & Advanced SEO | | LiseDE
Lise0 -
Null Alt Image Tags vs Missing Alt Image Tags
Hi, Would it be better for organic search to have a null alt image tag programatically added to thousands of images without alt image tags or just leave them as is. The option of adding tailored alt image tags to thousands of images is not possible. Is having sitewide alt image tags really important to organic search overall or what? Right now, probably 10% of the sites images have alt img tags. A huge number of those images are pages that aren Thanks!
Intermediate & Advanced SEO | | 945010 -
How Many Images on 1 Page Are Acceptable
Example I have a page with a slideshow of 35 pictures. They are all unique pictures and relevant to the page, have unique alt text, though no captions or description surrounding the images. Page also has a lot of unique written content. Question: is this large nr of pictures potentially overwhelming for search engines and they may think it is spammy and it would be a safer bet to only keep the top 10 pictures on such page? I did review this great whiteboard Friday - http://a-moz.groupbuyseo.org/blog/image-seo-basics-whiteboard-friday - and I noticed this at very end: "The other part, and I see this happen a lot especially with bigger clients, is when you put lots and lots of images on one page, like an image gallery, those pages tend to be very hard to get indexed. The reason for that is there's not a lot unique textual content. A lot of times it's just overwhelming to users. It doesn't provide a lot of benefit in a search result." My page has been indexed, but will ranking potentially be hurt and to play it safe I better reduce nr of pictures? I do understand the "do what is best for the user" scenario and that is what I am doing with a lot of amazing original pictures not found on any other website. However, with search engines we obviously have to consider how they operate as well. Thank you
Intermediate & Advanced SEO | | khi50 -
Exact keyword URL or not?
Hi all, I have a quick question about the proper use of permalinks. Let's say that I have a website about sports and I want to create an internal page dedicated to shoes. I know that the keyword "shoe" has 15.000 monthly visits, while the keyword "shoes" has 1.000 monthly visits. How do I have to name the internal page? http://www.example.com/shoe or http://www.example.com/shoes (with a final 's')? I would think that by naming the URL http://www.example.com/shoes, the search engine would consider that page for the keywords "shoe" and "shoes", but I am not sure about it. Should I create a URL that only focuses on one specific keyword ("shoe", in this example) or a URL that may encompass more than one keyword ("shoe" and "shoes")? I hope this is clear. Thank you for your time and help. All best, Sal
Intermediate & Advanced SEO | | salvyy0