Image Height/Width attributes, how important are they and should a best practice site include this as std

[Dan-Lawrence]

Hi

How important are the image height/width attributes and would you expect a best practice site to have them included ?

I hear not having them can slow down a page load time is that correct ?

Any other issues from not having them ?

I know some re social sharing (i know bufferapp prefers images with h/w attributes to draw into their selection of image options when you post)

Most importantly though would you expect them to be intrinsic to sites that have been designed according to best practice guidelines ?

Thanks

[Dan-Lawrence]

Thanks for confirming that Paul !

Ive also noticed that when using services like Buffer etc, to post socially, that the articles image is not being displayed as an option in the images to choose from, to display as the image in the post, Instead its only showing options like the site logo etc which we don't want.  I asked Buffer tech support and they said that if the images had height/width attributes then they should then be presented as image options to accompany the post

All Best

Dan

[ThompsonPaul]

Image h x w attributes don't affect the actual speed of your page load much, Dan. They do strongly affect the perceived speed to the user.

If the size attributes are included, the browser can leave a correctly-sized space for each image as the page gets rendered, even if the images haven't started to download yet. Then the rest of the page content flows in around the image "placeholders". (Images are always slower than text.)

If no image size attributes are present, the browser essentially ignores the placing of the images until the image files actually download, then redraws the whole page to add the space back in for the images.

This redrawing for the images means that text and other elements will move around on the page until all the images have downloaded and it has finished rendering. This gives the user an impression of a much slower page, since they can't start to read the content until it has stopped moving around. Done properly, the visitor can start reading the top of the page even while all the images lower on the page are still downloading.

So yes, obviously including height and width attributes for images is standard best practice for designing an effective on-page user experience.

Hope that helps?

Paul

P.S. As proof, Google thinks they're such a standard requirement that they have included a check for them as part of the scoring algorithm of their Google Page Speed tool.

[dotfly]

"How important are the image height/width attributes and would you expect a best practice site to have them included ?"

This is not the most important SEO thing in the world BUT according to your 2nd question

"I hear not having them can slow down a page load time is that correct ?"

That`s the point! The question related to this issue is how relevant the whole thing might be?

Modern browsers and broadband connections seem to make this insignificant but just in case there are some visitors which are not using the right settings they might get pictures unscaled and your whole site will be shown non-responsive... by the way, use responsive designs if you can to avoid that...

Ive always been told to use these parameters . even if you dont need it it ensures that your code is a little bit more perfect