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.
Sitespeed: Do images require width and height attributes?
-
Currently working on a sitespeed issue, and was wondering if not having width and height for images actually do cause a problem. We simply Photoshop the resolution we require for the image and add it to the page as is. I though this would actually speed it up, but I am getting from www.gtmetrix.com that we should have them.
What's your experience? Thanks!
-
Just came across a terrific resource that reminded me you'd asked about further reading, Ben.
Check out BrowserDiet for a huge collection of resources about tuning front-end performance of websites. (You'll see #6 talks about exactly your original question)
I can also recommend reading Steve Souder's two books - High Performance Websites and Even Faster Websites - both from O'Reilly. Souders is pretty much the leading specialist in this area. He's the creator of YSlow, one of the primary tools for measuring/analyzing site speed, and is now Head Performance Engineer at Google. His website is SteveSouders.com
That'll be more than enough to get you started. Lemme know if you're still hungry for more!
Paul
P.S. The report details from tests at webpagetest.org can also teach you a huge amount, and there's a forum there run by Patrick Meenan (who built webpagetest) which is just excellent. Patrick frequently answers questions personally.
-
you're welcome, hope your site will be speeding up a lot!!!
-
Yes, thank you. We size them all to what we want on the site so we are good there. Just got done doing it, and it did make a difference. Thanks guys!
-
as Paul correctly said, if your purpose is to improve the page speed just be sure that you're not resizing the images with css/html but that you're uploading the images in that dimensions.
An image of 10241024 resized to 100100 still weights as an 1024 image so my recommendation is to resize all those images to the desired dimensions, moreover if you can use an external cdn you'll save bandwith and have those images loading outside your website. That will help reducing the loadtime of the page.
-
Perfect-O! I completely get it now. Thanks Paul. You da man!
I thought it would be faster as in my mind it was more to read, but now that I understand the loading, I get it. Guess I need to start researching how a website loads. Have any resources I can read, to up my experience with this?
I've been in development but on an application side not website side.
-
The main reason PageSpeed and YSlow recommend including width and height for images is as much the perception of page speed as the actual load time, Ben.
When you include the image dimensions, the browser can draw out the "containers" that will hold the images, reserving the space for them while they download. The browser can then go on the paint the rest of the pages CSS and objects around those "containers" without having to go back and redraw the whole page once the images have downloaded and their sizes are then known.
This gives the user the illusion of a much faster, cleaner page load, and hence the impression of a faster website.
Does that make sense?
Paul
[Edited to add: You should still keep doing what you're doing to produce "size-as" images for your pages. You don't want to be resizing images with the html dimensions, just reporting in html the actual size of the image]
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
-
Text over image
Hello, I am creating an overlay on a image. Is it ok to write on this overlay in html or it is better to have the text not on a image for google and other search engines ? Thank you,
Intermediate & Advanced SEO | | seoanalytics0 -
How many images should I use in structured data for a product?
We have a basic printing website that offers business cards. Each type of business card has a few product images. Should we use structured data for all the images, or just the main image? What is your opinion about this? Thanks in advance.
Intermediate & Advanced SEO | | Choice0 -
Probably basic, but how to use image Title and Alt Text - and confusing advice from Moz!
I've been doing SEO on my business's site for years and have got good results. I've always used image Titles and Alt Text text. Our blog posts are image-intensive, often with 100-200 pictures (not surprising since we're photographers). For any given blog post, I've tended to have a uniform image Title for each image and then a more specialised Alt Text tag giving a description. A typical image on one of our blog posts would be like this: Image filename: wedding-photography-at-so-and-so-venue-001.jpg .... 002, 003 etc Image Title Attribute: Wedding Photography at So-And-So-Venue by Our-Company-Name - this would be the same for every image in the blog post. Alternative Text: Bride and groom exchanging vows during wedding ceremony at so-and-so-venue - this would be tailed for each image. So my question is - is this right? The Moz help page for image SEO is actually incorrect in one aspect: https://moz.com/ugc/10-tips-for-optimizing-your-images-for-search "Alt text (short for “alternative text”) is used to highlight the identity of an image when you hover over it with your mouse cursor. It also shows as text to all users when there are problems rendering the image." This is not the case. Hovering over the image in Firefox, Chrome, Edge and Opera ALL display the Image Title, NOT Alt Text. Thoughts?
Intermediate & Advanced SEO | | robandsarahgillespie0 -
Google doesn't index image slideshow
Hi, My articles are indexed and images (full size) via a meta in the body also. But, the images in the slideshow are not indexed, have you any idea? A problem with the JS Example : http://www.parismatch.com/People/Television/Sport-a-la-tele-les-femmes-a-l-abordage-962989 Thank you in advance Julien
Intermediate & Advanced SEO | | Julien.Ferras0 -
Google not Indexing images on CDN.
My URL is: http://bit.ly/1H2TArH We have set up a CDN on our own domain: http://bit.ly/292GkZC We have an image sitemap: http://bit.ly/29ca5s3 The image sitemap uses the CDN URLs. We verified the CDN subdomain in GWT. The robots.txt does not restrict any of the photos: http://bit.ly/29eNSXv. We used to have a disallow to /thumb/ which had a 301 redirect to our CDN but we removed both the disallow in the robots.txt as well as the 301. Yet, GWT still reports none of our images on the CDN are indexed.
Intermediate & Advanced SEO | | alphonseha
The above screenshot is from the GWT of our main domain.The GWT from the CDN subdomain just shows 0. We did not submit a sitemap to the verified subdomain property because we already have a sitemap submitted to the property on the main domain name. While making a search of images indexed from our CDN, nothing comes up: http://bit.ly/293ZbC1While checking the GWT of the CDN subdomain, I have been getting crawling errors, mainly 500 level errors. Not that many in comparison to the number of images and traffic that we get on our website. Google is crawling, but it seems like it just doesn't index the pictures!?
Can anyone help? I have followed all the information that I was able to find on the web but yet, our images on the CDN still can't seem to get indexed.
0 -
Attribution of port number to canonical links...ok?
Hi all A query has recently been raised internally with regard to the use of canonical links. Due to CMS limitations with a client who's CMS is managed by a third party agency, canonical links are currently output with the port number attributed, e.g. example.com/page:80 ...as opposed to the correct absolute URL: example.com/page Note port number are not attributed to the actual page URLs. We have been advised that this canonical link functionality cannot be amended at present. My personal interpretation of canonical link requirements is that such a link should exactly match the absolute URL of the intended destination page, my query is does this extend to the attribution of port number to URLs. Is the likely impact of the inclusion of such potentially incorrect URLs likely to be the same as purely incorrect canonical links. Thanks
Intermediate & Advanced SEO | | 26ryan0 -
Creative Commons Images Good for SEO?
I've been looking at large image packages through iStock, Getty, Fotolia and 123RF, but before spending a bunch of money, I wanted to get some of your feedback on Creative Commons images. Should be worried that something found on Google Images > Search Tools > Usage Rights section can be used without issue or legal threats from the big image companies so long as they are appropriately referenced? AND will using these types of images and linking to the sources have any affect on SEO efforts or make the blog/website look spammy in Google's eyes because we need to link to the source? How are you using Creative Commons images and is there anything I should be aware of in the process of searching, saving, using, referencing, etc? Patrick
Intermediate & Advanced SEO | | WhiteboardCreations0 -
Number of images on Google?
Hello here, In the past I was able to find out pretty easily how many images from my website are indexed by Google and inside the Google image search index. But as today looks like Google is not giving you any numbers, it just lists the indexed images. I use the advanced image search, by defining my domain name for the "site or domain" field: http://www.google.com/advanced_image_search and then Google returns all the images coming from my website. Is there any way to know the actual number of images indexed? Any ideas are very welcome! Thank you in advance.
Intermediate & Advanced SEO | | fablau1