Best practices: keywords in alt attributes

October 22, 2009

Topics: Accessibility.

This is certainly a subject that I’ve covered before — in fact, it’s something I would hardly choose to cover yet again if it didn’t continue cropping up as an important issue. The use of text in alt attributes is an extremely sensitive subject.

Today, the good folks at SEOmoz published an extensive article documenting their statistical findings on web site ranking factors, as gathered from the data in their LinkScape analysis tool. It’s a good article, and demonstrates some interesting results they’ve garnered from the data available in the extensive LinkScape database.

One of their major takeaways in the article was a little disturbing to me.

“Alt attributes of images are probably pretty important places to use your keywords[.]” Explaining (Some of) Google’s Algorithm with Pretty Charts & Math Stuff, October 22nd, 2009

I’m not in anyway disputing their results; their data indicates that placing keywords in alt attributes is of benefit to search engine rankings. Whether that’s true or not is irrelevant to me; I simply want to discuss how this information should be best used.

SEOmoz, of course, is a company dedicated to the study and practice of search engine optimization and marketing. Their goal is to learn what they need to know in order to best put into practice the promotion of web sites. That’s great. My goal, however, is to make sure that users with disabilities are able to use and access web sites successfully without having to jump through unnecessary or unhelpful hoops along their way.

This is a particular case where the SEO method must be used cautiously and selectively if at all. What I want to convey in this article is the fact that while using keywords in alt attributes may help your web site rank, it can also result in a significantly less accessible web site, if applied poorly.

What’s the problem with alt attributes?

While sighted users will never even be aware of an alt attribute value in normal web browsing, screen reader users depend on them. Excess verbiage can render an image-based menu unusable, as I observed in a recent site review at Practical eCommerce. The same unnecessary use of keyword terminology in contextual images can easily confuse or distract a user; and the use of keywords with spacer or ornamental images can cause a web site to be completely unnavigable.

It’s all a question of information overload: practically speaking, if a web site uses images to convey information, a screen reader user can’t disable them without rendering the web site unusable. If the site also fills other images with extra text, the same user may be overwhelmed by an unnecessary volume of keyword phrases.

The SEOmoz report does continue to remark that “Keyword stuffing may be holding you back,” and the overuse of keywords in alt attributes can certainly qualify as keyword stuffing.

You shouldn’t take away from this article that using a keyword in an image alt attribute is totally unacceptable. That’s really not the case: just be selective. I wouldn’t condemn you for using the text “About ProductName” instead of “About” for a navigational image, or using a sensible alt attribute for a contextual image, such as “Woman using our ProductName.” Just remember that keyword stuffing is keyword stuffing, wherever you put the words.

And never place any value in the alt attribute for a purely decorational or spacing image. Please. Just an empty attribute.

22 Comments to “Best practices: keywords in alt attributes”

  1. Very good article. I always use both alt and titles, but to be honest I hate using title tags sometimes because I hate how it shows up when you hover the images. I wonder if there is a way to still put title tags, but hide it. I have that issue with flash as well. It’s very annoying to put flash title’s in because it shows you the title on hover of the flash. I don’t want that! Do you feel it’s necessary to do both? Obviously I agree if it’s a blank image, don’t put an alt, but for an image that actually has meaning.

  2. “It’s all a question of information overload: practically speaking, if a web site uses images to convey information, a screen reader user can’t disable them without rendering the web site unusable. If the site also fills other images with extra text, the same user may be overwhelmed by an unnecessary volume of keyword phrases.”

    Thanks for that information. As someone who believes (even at the cost of xhtml strict not validating because of “aria: required”) for the sake of screen readers, you’ve just enlightened me on why NOT to stuff images with keywords. I just found your site and have a wealth of information to sift through on accessibility. Thanks! I’m subscribing to your feeds!

  3. the information that u say already heard in some way anyway thanks for your great information

  4. Hey joe I read alot of your articles and was just curious do you know the difference between a alt and title tag for linking purposes of images? Which one you believe would be most beneficial. Thanks in Advance Joe you have a great blog.

  5. I thought alt attributes will be useful for fetching hits from the search engine but after reading your post I need to rethink. Thanks a lot for sharing this useful information and I’ll inform my friends to follow it.

  6. I know for a fact that naming your alt tags for internet marketers in general is only about search engine optimization. It is unfortunate, but any possible way to gain more leverage is going to be an incentive. I mean if doing your alt tags in this way will get you to the first page, and bump you up ahead of a guy that is a little more cautious about his alt tags then you are going to do it. In my designs I make sure to name things as they are, and use my keywords when applicable. But until this does not have a direct effect on rankings I don’t think the general public will be implementing the appropriate practices.

  7. katlyn, ATT Uverse Reviews; November 8, 2009 at 12:59 am

    Very interesting article, thanks for the pointers. I love this post. Very informative..thanks. I never realized that having to much alt attribute could be considered key word stuffing.

  8. Thanks for sharing with us such interesting article. Accesibility issues are absolutely important!

  9. If the information is already communicated by other means, then the image doesn’t add value for the disabled; only for visual users, as an alternate way of communicating the information. However, if only part of the information has been communicated elsewhere, you still need to include the entirety of the information in the alt attribute, for the sake of context.

    Also — thanks for the heads up! I missed that one when I stripped the tabindex attributes, clearly. Also, thanks for the suggestion on the comment subscription option.

  10. Joe, if an image (e.g statistic table) is supplemental to content. But there are some texts in the content have already explained the statistic counts. What is the best for the alt attribute?

    [OOT]:
    a. Your tabindex is still exist in name input.
    b. Should the “notify me …” line be placed before the submit button? Usability reason, I think. 🙂

  11. I liked reading this article very much and I enjoyed the following discussion. It may be a seo boost to use alt attributes in images, but if we want our website to be fully usuable for people with an impaired vission, we should then do an accurate use of these attributes in order not to leave these people away from our site.

  12. There’s no “recognized standard,” as such, for alt attribute values. The variety of uses of images is broad enough that defining straightforward guidelines for exactly what is acceptable or appropriate is somewhat unmanageable. However, for many images, the best practice rule of thumb is very straightforward. For images portraying text or specific information, the text should be contained in the alt attribute. For images which serve a purely ornamental function, the alt attribute should be left blank.

    Images which are supplemental to an article without conveying specific information, however, are more complicated. They are a grey area where the value of the alt attribute requires individual attention for every situation.

  13. Hmm. Thanks for this conversation. I guess it all boils down to thinking about someone else before yourself. After all – what is the alt text for, for heavens sake? Would a client really want to ride roughshod over an unsighted person’s ability to visit their site – and be seen doing that, or would they want to exercise a little sensitivity – and be seen to be doing that? Is there a publicly recognised standard for good alt text?? If not, maybe there should be.

  14. I’m fully aware of the difficulties in web site maintenance and code control which impact a site. In fact, I don’t generally feel that it’s the web developer who’s to blame, specifically – the fault is always, always shared. Some part of it goes to search engines, but I’m not convinced that’s a great share. If you read the report, it indicates that keyword stuffing is not, in fact, an effective technique — so there’s some small balance between keyword use in alt attributes and keyword stuffing. Additionally, the specific balance point on that is simply not addressed — it’s an unknown issue.

    The main fault goes to ignorance, simply and completely. Google can’t really police accessibility because accessibility is not programmatically determinable. Without individually examining every alt attribute, Google can’t really know whether the attribute is valuable or not, except by using exactly the same profile for analysis that they would for any other block of text. That is what I’d hope they do.

    Do we spend our own free time repairing work that someone else has been paid to do? Especially when the client couldn’t give a sh*t? I personally have stopped doing that, because 1) the client couldn’t give a sh*t, 2) and i can’t afford to do free work on every website I see that is poorly acce

    No. Of course not. Accountability can only go so far — poor accessibility is so incredibly pervasive that you could easily spend months doing nothing but fixing issues on a website where you were hired to make a couple of quick content changes. It is not your responsibility to fix the website; it’s the owner’s responsibility. I feel strongly that you should inform them of the problem, but if they aren’t interested in funding the changes, that’s where your obligation ends.

    I do still do minor things, when I can — if I’m making an update to a site, I’ll do little things to at least make that section better than it was before, if it’s not any serious extra effort. And, similarly, if I’m asked to do something which will specifically compromise the accessibility of a site I let the client know that I won’t do it. I appreciate, however, that this isn’t a position everybody can take.

  15. I totally agree Joe. But there’s a huge gap in a building a website for yourself (and caring about its accessibility) and building a website for a company/individual who doesn’t give a sh*t, is totally oblivious to the World of accessible websites, and/or is 100% profit/ranking driven.

    Google shares in the responsibility because this is a signal for ranking; but Google did not build your web site for you and make the decision to include these terms.

    That is right Joe – but I (and many others) often work on pre-existing websites where someone else has built and made the accessibility/SEO decisions. What are we to do when we’re NOT being paid to to anything accessibilty-related, and we’re being paid ONLY for some simple maintenance work, or performance optimising, but we see poor accessibility and keyword alt stuffing while we’re code-deep? Do we spend our own free time repairing work that someone else has been paid to do? Especially when the client couldn’t give a sh*t? I personally have stopped doing that, because 1) the client couldn’t give a sh*t, 2) and i can’t afford to do free work on every website I see that is poorly accessible (even though I do want to make the web world a better place for everyone).

    Code-control/ownership is a huge part of the problem – even where one does the original website build, that doesn’t mean one maintains control over it. So even where designers/developers build a considerate, constructive, accessible website, that’s often where their involvement with the website ends, and then several different designers/developers maintain/modify/edit the work over the website’s lifetime. And egad, when a an SEO expert is brought in to make the website perform better IN GOOGLE for that businesses KEYWORD RANKINGS, inevitably a lot of hard work and accessibility love can be instantly undone.

    And irrespective of morals and responsibilities (yes accessibility IS a responsibility), business is business, and times are tough globally. Another sad truth is that vision impaired readers are a miniscule % of website traffic. It can be difficult to justify to moral-less penny pushers that additional funds should be spent to cater for a very, very small % of their visitors.

    So again, while I don’t pretend to be an expert or have the solutions, I think Google could (and SHOULD) play the largest part in the biggest accessibly fix on the WWW. They SHOULD be more responsible and made more accountable.

    While alt’s = SEO consideration, and while keyword stuffing alt’s (seem to) work on some SEO levels, and while accessibility is an optional element, accessibility will rank second to SEO most of the time; not by EVERYONE, and certainly not by me, but definitely by those who don’t care, and/or don’t know any better . That I do know.

    Sad but true.

  16. While Google continue to use the alt attribute as a ranking factor, those who Rank for a living will continue to use it. And no offense to the accessibility activists (I myself care, and have a friend who 100% vision impaired) you cannot blame them for doing so.

    Actually, I can blame them, and I will. Google shares in the responsibility because this is a signal for ranking; but Google did not build your web site for you and make the decision to include these terms.

    Frankly, keywords in alt attributes should be a ranking signal; but the boundary between keyword stuffing needs to sit at a very low threshold.

    There’s nothing in the SEOmoz article which might indicate that keywords in alt attributes approach a threshold for keyword stuffing sooner than terms elsewhere; but this is something which I think should be addressed.

    It’s absolutely true that Google could eliminate the problem entirely — but I don’t think it’s that simple. In fact, I don’t really think that Google’s ranking factors are the problem — the problem is what people think they need to do in order to be successful ranking with Google. If people think that image alternate texts are important, they will be abused.

    I just want people to understand the consequences.

  17. So, if it is the case that keyworded alt attributes are both SEO-advantageous and counter-accessible, why aren’t Google more accountable?

    While Google continue to use the alt attribute as a ranking factor, those who Rank for a living will continue to use it. And no offense to the accessibility activists (I myself care, and have a friend who 100% vision impaired) you cannot blame them for doing so.

    The problem is if an employer/business is paying you for SEO services, and they don’t care for, or are paying for accessibility, what can you do?

    The single biggest movement should come from Google, shouldn’t it? In one fowl swoop (nullifying alt attribute SEO considerations) they can make make the Internet more accessible and less keyword spammy!

    It is sad and less-than-optimistic that we’re in 2009 and keyword spamming is still so effective.

  18. I agree completely Joe. This is one of those balancing act things. There’s nothing specifically wrong with using a keyword in an alt attribute and I won’t question the SEOmoz findings. You just have to think about the people who rely on those alt attributes first.

    The problem when SEOmoz reports something like that is some will take the idea too far and think it’s in their best interest to stuff keywords. Hopefully most people will think users first and spiders second.

  19. Nice to be back once in a while! Occasionally, work lets me out of the cage 😉

  20. And nice to see you here, Marco!

  21. It’s a pretty key difference in goals — although I do want to emphasize that the article did not say “put keywords in your alt attributes,” it simply said that having keywords in your alt attributes is effective for SEO.

    Of course, being SEOmoz, they may as well have said that.

    I can’t say that it was wrong to come out and say “this is what the data shows,” but boy I wish they would also have said “but these are the problems caused by actually doing it.”

  22. Wow. It just goes to show you some of the disconnects between SEO and accessibility. Ouch!