Can the alt attribute for an img tag be empty?

**Mounty** · Apr 27, 2009, 13:24

I believe the img tag requires the alt attribute to validate the markup, but is alt allowed to be an empty string?

My validation tool seems to think it's ok, but I always thought it was required incase the image was missing

**AlexDawson** · Apr 27, 2009, 13:31

It can be empty, but you should always try to provide alternative text unless you have a seriously good reason not to do so. Be warned that by excluding a complete alt tag, visually impaired users will be unable to know that you have a picture in that placement.

**Mounty** · Apr 27, 2009, 17:36

ok then fair enough

cheers

**felgall** · Apr 27, 2009, 18:06

Usually an emtyp alt attribute indicates that the image is purely decorative and ought to be added by the CSS rather than the HTML. Those in the HTML are usually there to convey some information and that information would need to go in the alt attribute for those who don't see the image.

**AutisticCuckoo** · Apr 27, 2009, 21:47

The alt attribute provides the text equivalent (alternative) for an image. In other words, it should convey the same information as the image does (in that context).

If an image doesn't convey any relevant information in a particular context, the text equivalent should be empty. Thus, alt="".

**Stomme poes** · Apr 28, 2009, 00:58

Be warned that by excluding a complete alt tag, visually impaired users will be unable to know that you have a picture in that placement

They would know it's there if they have a screen reader. It'll say "graphic".

On a current site I've found myself using alt="" quite a lot. The reason being, background images can't be floated, where the text wraps around it, but the images are definitely decoration. Are there any good tricks for moving these things into the CSS?

**AutisticCuckoo** · Apr 28, 2009, 02:52

Originally Posted by Stomme poes

Are there any good tricks for moving these things into the CSS?

Not really. You could have an empty floated div and set the image as a background on that, but what would be the point?

**simon14593** · Apr 28, 2009, 03:09

In a nutshell, alt tags are not important for validation, however, they are very important for both accessibilty and SEO.

**AutisticCuckoo** · Apr 28, 2009, 03:21

Please, people, it's an alt attribute, not an <alt> tag.

**simon14593** · Apr 28, 2009, 03:27

Originally Posted by AutisticCuckoo

Please, people, it's an alt attribute, not an <alt> tag.

LOL. Good point. Alt attribute was what I meant.

**AutisticCuckoo** · Apr 28, 2009, 03:30

My comment wasn't directed to you personally, Simon. Too many people use the same misnomer, even people who allegedly are professionals. It's as if a medical doctor would refer to the heart as a gland.

**AlexDawson** · Apr 28, 2009, 06:59

Originally Posted by AutisticCuckoo

It's as if a medical doctor would refer to the heart as a gland.

Well mine swells and excreets stuff every second of every day!

I know it is an attribute rather than "tag" but I was still half asleep when I wrote it

**Dan Schulz** · Apr 28, 2009, 09:59

Originally Posted by Stomme poes

They would know it's there if they have a screen reader. It'll say "graphic".

On a current site I've found myself using alt="" quite a lot. The reason being, background images can't be floated, where the text wraps around it, but the images are definitely decoration. Are there any good tricks for moving these things into the CSS?

I use empty SPANs for that on the rare occasions I actually need to use them.

**Blake Tallos** · May 2, 2009, 05:28

Originally Posted by AutisticCuckoo

Please, people, it's an alt attribute, not an <alt> tag.

Hahaha, I swear it gets better everyday tommy.

Examples of Attributes -

Code HTML4Strict:

Alt,align,abbr,cellpadding,cellspacing,height,id,label,href,onblur,onclick,onload,onmousedown,onmousemove,

Good point though. It really is important to learn the differences because if we didn't what would be though point right?

**devbanana** · May 2, 2009, 05:43

Originally Posted by Stomme poes

They would know it's there if they have a screen reader. It'll say "graphic".

Not at all true if the alt attribute is empty. It will say nothing.

**AutisticCuckoo** · May 2, 2009, 08:40

Originally Posted by devbanana

Not at all true if the alt attribute is empty. It will say nothing.

Yes, but the question was how screen readers handle an omitted (i.e., missing, not existing-but-empty) alt attribute.

**devbanana** · May 2, 2009, 08:57

Originally Posted by AutisticCuckoo

Yes, but the question was how screen readers handle an omitted (i.e., missing, not existing-but-empty) alt attribute.

Same as if it is empty. I thought someone believed it would say something when encountering an image if it had an empty alt attribute. But whether it is empty or non-existent altogether, it will be as though the image is not there.

**AutisticCuckoo** · May 3, 2009, 08:23

I've heard a screen reader (may have been Window-Eyes, not sure) that would spell out the image URL (after saying the word 'image') in the absence of an alt attribute. That was a few years ago, though, so perhaps newer versions ignore it.

**devbanana** · May 3, 2009, 09:08

Originally Posted by AutisticCuckoo

I've heard a screen reader (may have been Window-Eyes, not sure) that would spell out the image URL (after saying the word 'image') in the absence of an alt attribute. That was a few years ago, though, so perhaps newer versions ignore it.

In JAWS (which is what I use), it has an option to do that, but by default it reads the alt attribute and ignores it otherwise.

The only time it'll read the URL is if the image is within a link. But if someone neglected to put in an alt attribute, it is often the case that the image has a cryptic name as well, so it reveals no more information about the target of the link.

For instance, on this page, the five links after the logo have no alt attributes, so I hear something like this:

Link graphic ss/sapphiresteel_pagegfx_r2_c4 On mouse over
Link graphic ss/sapphiresteel_pagegfx_r2_c5 On mouse over
Link graphic ss/sapphiresteel_pagegfx_r2_c7 On mouse over
Link graphic ss/sapphiresteel_pagegfx_r2_c9 On mouse over
Link graphic ss/sapphiresteel_pagegfx_r2_c11 On mouse over

Luckily, not all of their links are like that.

**kikykuang** · May 5, 2009, 01:52

I think you should not empty

**Blue Sky** · May 5, 2009, 02:52

is important for seo as well i believe

**Stormrider** · May 5, 2009, 03:43

Personally, I think the majority of alt attributes should end up being empty. Depends on the type of site you have, but a LOT of images are only used for decoration, even if they are related to the content, it's often just a photo to spice up the look of a page. It's actually fairly rare (again, depending on the site) for a photo to be a part of the content, I find. Even then, a lot of diagrams have a caption, which negates the use of alt text anyway (you wouldn't want a screen reader to read the same thing out twice...)

A lot of people get 'text alternative' mixed up with 'description', and they are not the same thing.

I would argue that the majority of alt attributes should be empty if they are being used properly.

**Stevie D** · May 5, 2009, 03:58

Originally Posted by Mounty

I believe the img tag requires the alt attribute to validate the markup, but is alt allowed to be an empty string?

My validation tool seems to think it's ok, but I always thought it was required incase the image was missing

Yes, that is all absolutely true. Any <img> element must have an alt attribute, but it can be empty (ie alt="") if that's appropriate.

If the image contains information that people would benefit from seeing, you need to put some meaningful text in - but if the image is purely decorative, or is simply an icon illustrating the adjacent text, it's best to leave it empty.

What you have to ask yourself is - if you were browsing the page without images (whether because you can't see them, you have images turned off, or the image just doesn't load properly), would you want to know (a) that there was an image there, and (b) what was in the image? If not, it's fine to leave the attribute empty.

http://reference.sitepoint.com/html/img/alt

**AutisticCuckoo** · May 5, 2009, 03:59

Originally Posted by Stormrider

Personally, I think the majority of alt attributes should end up being empty.

I agree.

Originally Posted by Stormrider

A lot of people get 'text alternative' mixed up with 'description', and they are not the same thing.

Exactly!

I would recommend those of you who are unsure about how to use the alt attribute to read Must I have an ALT attribute for every image? in the HTML FAQ. Compare the four different scenarios where a particular image is used, and note how very different the text equivalent is in each case.