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://moz.com/community/q/how-important-is-the-file-extension-in-the-url-for-images
It's not
https://moz.com/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.
Got a burning SEO question?
Subscribe to Moz Pro to gain full access to Q&A, answer questions, and ask your own.
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
-
Changing Url Removes Backlink
Hello MOZ Community, I have question regarding Bad Backlink Removal. My Site's Post's Image got 4 to 5k backlinks from unknown sites and also their is no contact details on their site so that i can contact them to remove. So, I have an idea for which i want suggestion " If I change the url that receieves backlinks" does this will remove backlinks? For Example: https://example.com/test/ got 5k backlinks if I change this url to https://examplee.com/test-failed/ does this will remove those 5k backlinks? If not then How Can I remove those Backlinks? I Know about disavow but this takes time.
Intermediate & Advanced SEO | | Jackson210 -
Redirect old image that has backlinks
Hi Moz Community! I'm doing an audit of a website and did a backlink analysis. In the backlink analysis, there is an image that has 66 backlinks but the image doesn't exist on the website anymore (it was on a website that was created in 2011 - 2 web launches ago). I don't believe a 301 redirect will work for an image that doesn't exist anymore. How would I redirect the image URL (it's WordPress so we have a specific URL that other websites are linking to but get 404 errors) without going to each individual website and requesting they change the URL link? Any advice or recommendations would be great. Thanks!
Intermediate & Advanced SEO | | BradChandler1 -
Help with facet URLs in Magento
Hi Guys, Wondering if I can get some technical help here... We have our site britishbraces.co.uk , built in Magento. As per eCommerce sites, we have paginated pages throughout. These have rel=next/prev implemented but not correctly ( as it is not in is it in ) - this fix is in process. Our canonicals are currently incorrect as far as I believe, as even when content is filtered, the canonical takes you back to the first page URL. For example, http://www.britishbraces.co.uk/braces/x-style.html?ajaxcatalog=true&brand=380&max=51.19&min=31.19 Canonical to... http://www.britishbraces.co.uk/braces/x-style.html Which I understand to be incorrect. As I want the coloured filtered pages to be indexed ( due to search volume for colour related queries ), but I don't want the price filtered pages to be indexed - I am unsure how to implement the solution? As I understand, because rel=next/prev implemented ( with no View All page ), the rel=canonical is not necessary as Google understands page 1 is the first page in the series. Therefore, once a user has filtered by colour, there should then be a canonical pointing to the coloured filter URL? ( e.g. /product/black ) But when a user filters by price, there should be noindex on those URLs ? Or can this be blocked in robots.txt prior? My head is a little confused here and I know we have an issue because our amount of indexed pages is increasing day by day but to no solution of the facet urls. Can anybody help - apologies in advance if I have confused the matter. Thanks
Intermediate & Advanced SEO | | HappyJackJr0 -
Image URLs - best practice
Hi - I'm assuming image URL best practice follows same principles as non image URLs (not too many files and so on) - I notice alot of web devs putting photos in subdomains, so wonder if I'm missing something (I usually avoid subdomains like the plague)!
Intermediate & Advanced SEO | | McTaggart1 -
Does Google Read URL's if they include a # tag? Re: SEO Value of Clean Url's
An ECWID rep stated in regards to an inquiry about how the ECWID url's are not customizable, that "an important thing is that it doesn't matter what these URLs look like, because search engines don't read anything after that # in URLs. " Example http://www.runningboards4less.com/general-motors#!/Classic-Pro-Series-Extruded-2/p/28043025/category=6593891 Basically all of this: #!/Classic-Pro-Series-Extruded-2/p/28043025/category=6593891 That is a snippet out of a conversation where ECWID said that dirty urls don't matter beyond a hashtag... Is that true? I haven't found any rule that Google or other search engines (Google is really the most important) don't index, read, or place value on the part of the url after a # tag.
Intermediate & Advanced SEO | | Atlanta-SMO0 -
Weird 404 URL Problem - domain name being placed at end of urls
Hey there. For some reason when doing crawl tests I'm finding pages with the domain name being tacked on the end and causing 404 errors.
Intermediate & Advanced SEO | | Jay328
For example: http://domainname.com/page-name/http://domainname.com This is happening to all pages, posts and even category type 1. Site is in Wordpress
2. Using Yoast SEO plugin Any suggestions? Thanks!0 -
301 Redirection and apostrophes in URLs
Hi I am experiencing trouble getting any redirects with apostrophes in the URLs to 301 redirect in order to eliminate 404 errors. I have tried replacing the instance of the apostrophe in the source URL field to %27 and variations of this but to no avail. The site is a wordpress site (the old URLS are legacies from the old Business Catalyst site) and I am using the redirection plug in. I have gone into some detail with a helpful soul here http://wordpress.org/support/topic/how-to-deal-with-apostrophes-in-source-url but unfortunately to no result. If anyone has any idea how to solve this puzzle I would be grateful for the help. Example: http://www.tesselaars.com/blog/Inside_Flowers/post/Online_Marketing_for_Florists_Part_1%E2%80%93_A_Website_You_Won%27t_Regret/
Intermediate & Advanced SEO | | Seamoose0 -
URL Length or Exact Breadcrumb Navigation URL? What's More Important
Basically my question is as follows, what's better: www.romancingdiamonds.com/gemstone-rings/amethyst-rings/purple-amethyst-ring-14k-white-gold (this would fully match the breadcrumbs). or www.romancingdiamonds.com/amethyst-rings/purple-amethyst-ring-14k-white-gold (cutting out the first level folder to keep the url shorter and the important keywords are closer to the root domain). In this question http://www.seomoz.org/qa/discuss/37982/url-length-vs-url-keywords I was consulted to drop a folder in my url because it may be to long. That's why I'm hesitant to keep the bradcrumb structure the same. To the best of your knowldege do you think it's best to drop a folder in the URL to keep it shorter and sweeter, or to have a longer URL and have it match the breadcrumb structure? Please advise, Shawn
Intermediate & Advanced SEO | | Romancing0