I see mixed opinions on this. Some say that ALT is now useless like the meta tag and some say it is very important to use ALT tag. Some SEO analysis tools report error if ALT tag is not described. So i have a few questions regarding it…
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Please please please remember that there is no such thing as an alt tag. HTML has no <alt>. It is an alt attribute, or alt text if that’s easier to say and type.
The alt attribute is not an SEO tool, it’s an accessibility tool. It’s purpose is to allow people/machines who can’t see the images to understand the page. If you’re looking to go keyword stuffing (aka spamming) then just forget it. Google is usually smart enough to know when it looks like you’re giving genuine alt text and when you’re spamming, and if it thinks you are spamming then it will treat your site with the contempt it deserves…
So, what should you be including in your alt text? A simple description of the image and/or its function, that would be appropriate for a user who couldn’t see the image itself, so that the page still makes sense.
- What is the appropriate length for ALT tag keywords ?
Whatever is needed to take the place of the image. In most cases this will be brief, because while a picture may be worth a thousand words, it’s rarely necessary to use more than a few words to give sufficient detail.
- Shall i use normal sentences or should use underscore of hyphens instead of spaces
Why on earth would you want to use underscores or hyphens? Alt text is supposed to be human-readable and friendly. If someone is using, for example, a text-to-speech reader, do you think it will cope better with “Sunny beach in Mexico” or “sunny-beach-in-mexico”? It’s rarely necessary to write in full sentences, because you won’t usually be writing that much, but just use a normal writing style.
- Does the name of the image file and its format matters ?
The image format will make no difference. The image name can make a difference to SEO, although if you’ve got everything else right then it shouldn’t be a huge difference. By that I mean … if you have no alt text and no meaningful surrounding context that Googlebot can understand, then changing “img10432.jpg” to “mexico-beach-4.jpg” is vitally important. But if you’ve already got good alt text, a caption that describes the image, and other text around it, all of which points to it being a beach in Mexico, then Googlebot will be less concerned about it being called “img10432.jpg” because it can still figure out what the image is of.
- Any other suggestion to handle image rich site ??
It’s a good idea to try to include some descriptive text where you can. It makes it easier for both people and search engines to understand your page if there are actual words, sentences and paragraphs than just a series of pictures.[/font]
Ok got it… thanks for the detailed description…
One thing to remember is that those who don’t see the image will have the alt text substituted for it - the best alt text will match in with the text before and after the image so that the person reading the content will not even realise that the text has an image alternative.
[FONT=verdana]Just one other point to add to the good advice already given …
You don’t need any Alt text for images used merely for decoration. I’m thinking of things like rounded corners and similar bits of furniture. In these cases, do include an Alt attribute, but set it to an empty string. That way, your page will validate correctly, but it won’t clutter a screen reader with useless information.
Mike[/FONT]
It would be interesting to know from someone who has tested sites using a screen reader how these images are read. If they are ignored leaving the alt attribute out is fine, but if the screen reader says there is an unknown image will the user (so used to terrible websites) think that it could be important?
I found a couple of interesting articles about this subject, firstly on how screen readers read things and then specifically on [URL=“http://webaim.org/techniques/images/alt_text”]alt text. As far as I understand it, alt=“” is ignored by a screen reader as an empty string, but if the alt is missing, it will attempt to substitute something, such as the file name or adjacent text. So the alt attribute should always be used, even if it’s empty.
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That’s what I’ve always understood as well.
Mike[/FONT]
well, the alt attribute is listed in google’s guidelines and therefore if you want to walk along the google’s guidelines then you should probably use it. Using alt attribute makes search engines understand what the image is all about and therefore if anyone searches for that description which you give in, google displays your image. Its a part of image optimization technique. So if you want to get traffic from image searches, you should probably optimize your image. And for the length of the attribute, well, you should keep it as short as possible but make sure you don’t add pure keywords in the tags or descriptions.
ALT tag is most important for Image optimization. It also make a good effect on SEO. Search engine can not read image so that we use ALT tag to describe about Image and search engine can easily read this and index very easily. The length of Alt tag is not so restricted but it is better to use 20 words in ALT tag.
Thanks
Farabi, <snip>
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Where on earth did you hear that? As has already been explained, the alt text is
and as to length, that should be
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There are some great answer above, I just wanted to add that alt tags are the main way Google and other search engines know what the images are about. If you want to rank your images in Google image search, then these are an absolute must.
Forget the search engines - they are of secondary importance with respect to alt text. Of far greater importance are all of the real people who will be visiting who for one reason or another cann ot see the images. They are the ones that the alt text is for, not the search engines.
Well, he did say IF we want our images to rank. I’d think about the people looking at my website first before anything else.
About the alt attribute, I’d rather look at it by its original function: a text that is displayed if in case the image doesn’t load, or you’re browsing using a text-only browser.