Alt tags - will they harm or help my site?

[eddiebooth]

Hi,
one of my sites was slow at loading so I reduced the image sizes using Ifranview.
I didnt notice, but when I saved the new-size images the existing alt tags had disappeared.
My site was loading quicker after this, so today I decided to add the alt tags back in on my desktop with the intention of uploading them again in bulk later.
I was surprised to spot that when I added alt tags the file sizes jumped massively, e.g. from 11kb to 18kb.
My concern now is that if I upload these is my site going to slow down again, in which case I need to decide if I am better with or without the alt tags.

[Slowdive]

Hey Eddie what you building in?
If its html your code should look something like this <img src="XXXX/XXXX/.jpg" width="144" height="189" alt="merry xmas" /> but html has an easy way to define alt tags.
Then for wordpress you can add tags, descriptions, titles and more depending on theme.
So let me know what your working in and I will guess at your best alt tagging solution, its probably not infran views tags.
Let me know.

[Kay]

I'm not a techie so I don't know the answer, but do Alt Tags not also have some implications for website accessibility?

[JJMcClure]

Heh, I was involved in a massive conversation about this exact subject on Sitepoint recently. The general feeling was that the Alt Description Atribute (it's not actually a tag) might help with SEO, but not very much. Since it's a signal that's under the control of the webmaster themselves, it's never going to help much. If you spam it to death with keyword phrases that's probably not going to help and most liekly will get you penalised for keyword stuffing....

It's definitely an Accessibility issue. People who have the images turned off or who may be using screen readers will benefit from a good descriptive Alt.

[Slowdive]

Some browsers aimed at accessibility for the visually impaired will pass the alt tag on as the image description as well yes. However its unlikely they would be able to parse infran views tags. Then again was not aware infran view could tag images either so I am guessing.
In theory the alt image tag should explain precisely what the image is so if its a dog chasing a ball, it should state alt= labrador dog chasing a ball.

Wordpress has confused this some as it uses image tags in such a variety of ways, it has also however made it easy for anyone to cover their seo bases in that regard. The new themes from Wp do such a great job of so many aspects of SEO that it wont be long before a SEO specialist manages traffic, links and explains what your WP theme is doing. Well more or less

[crabfoot]

Ignoring Goog, the other search engines still use title and description tags for display in the search results. If you want to tell someone what your page is about when they find it through Yahoo or Bing, you want the description to be accurate - and if you use those tags, they should be different for each page, otherwise the spiders would (historically) lump the pages together.

They also attach great importance to alt tags whether they are accurate or not. I've got some dud pics on one site - colored squares with text on them, the alt tags claim they are relevant pics, the spiders are blind ...

[Slowdive]

The alt attribute should still be useful for keyword density which although fast becoming outdated, I do not mind have some long tail keywords in my page and still like to use my terms. So I say by all means use it just sensibly and in a way that would benefit accessibility

[EDIT] The photo (under On-Page Keyword Useage) from SEOmoz sums it up nicely

[grynge]

Are you mixing up property attributes for the file rather than an alt tag?

An alt tag won't add any file size to a file, changing the attribute will change filesizes, for images file attributes I find they can be useful when uploading large amounts of images as wordpress and other cms's can automatically pick up the image file attributes.

[Chabrenas]

I thought that ALT description helped get an image in G's image index.

[tke71709]

I'm very confused about how alt tags on images have resulted in a jump from 11k to 18k.

Unless you have thousands of images or incredibly overstuffed tags, a few dozen extra characters for each image shouldn't have that sort of effect.

Maybe load one version of the non-alt tag page and one with the alt tages and share the links to the two here.