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Re: Characters in Alt attribute

for

From: Jukka K. Korpela
Date: Aug 17, 2005 3:20PM

On Wed, 17 Aug 2005, Mamta Tandel wrote:

> Does anyone know the maximum length of characters to be specific in alt
> attribute?

There is no theoretical maximum, but 50 characters is a useful practical
limit. Exceed it only if the benefits to users using advanced browsers
like Lynx (which has no problems with long alt texts) outweigh the
problems of people who use IE in a mode where images are not displayed.

> In addition, what number of characters do you suggest should be
> ideal keeping accessibility and usability in mind?

As many as necessary, but not more.

In practice, most alt texts can be written much shorter than 50
characters, whereas some content-rich images really correspond to a
thousand words. There's little point in putting those thousand words into
an alt attribute (which is plain text and cannot even contain paragraph
breaks!). Instead, put the words elsewhere and link to them suitably.
This often lets you use an empty alt text (since alternate content is
offered via the link) or a purely labelling alt text.

--
Jukka "Yucca" Korpela, http://www.cs.tut.fi/~jkorpela/