The Alt attribute is an attribute for displaying alternative text for images, and is one of the important elements in
SEO
. However, there are probably many people who don’t know what the Alt attribute is in the first place, or how to write it properly.
Therefore, in this article, we will explain the overview of the Alt attribute and how to write it. We will also introduce detailed tips on writing Alt attributes and their relationship with SEO. If you want to get even the slightest advantage in SEO, please use this as a reference.
What is the Alt attribute?
First, let’s start with an overview of the Alt attribute. Alt attribute is an attribute for displaying alternative text for images. When uploading images to
WordPress
, the part that is displayed as alternative text becomes the Alt attribute.
The Alt attribute is used when uploading images with input and img elements. If the image content does not have an Alt attribute, the meaning of the image will not be displayed to
search engines
or users if the image is not displayed for some reason. However, by including the Alt attribute, the alternative text will be displayed in the uploaded part of the image even if the image is not displayed.
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Difference between Alt attribute and title attribute
The Alt attribute is an attribute that is often confused with the title attribute. It is true that their roles are similar, so it is important to properly understand the differences. I will briefly describe the differences between each. .
- Alt attribute: text that represents the image itself
- title attribute: Text that supplements the image or image description
In other words, the Alt attribute is the text used to describe the content of the image, and the title attribute is the text used to supplement the image’s features. Also, although the Alt attribute can only be set for images, the title attribute can be set for text other than images.
For example, suppose you have an image displayed and you hover over it. At that time, a popup called a tooltip may be displayed above the image, and the title attribute is used there. Therefore, it is important to understand that the Alt attribute can only be set on images, while the title attribute can also be set on text elements other than images, such as speech bubbles.
How to write the Alt attribute
Writing the Alt attribute is very simple. Just submit the HTML below and the Alt attribute will be displayed.
<img src=”Image URL” alt=”〇〇“>
If you enter text in the 〇〇 part above, it will serve as the Alt attribute. Additionally, if you are running a website using WordPress, you do not need to write
the HTML
above; if you enter text in the alternative text section, it will be displayed as the Alt attribute.
Tips on writing Alt attributes
So far, we have explained the overview of the Alt attribute and how to write it. From here, I will explain the following two tips when writing the Alt attribute.
- Describe image features
- Don’t stuff keywords
Let’s look at each in turn.
Describe image features
First, it is important that the Alt attribute describes the characteristics of the image. Alt attributes that contain text other than image characteristics are often seen, but these are inappropriate. For example, let’s say you upload an image of Mt. Fuji within the text. Possible Alt attributes in this case are as follows:
<img src=”Image URL” alt=”Mt. Fuji”>
Here, we are setting an Alt attribute that describes the characteristics of the image “Mt. Fuji.” The reason why we see cases where Alt attributes other than image characteristics are set is because there are cases where images are used that are unrelated to the main text.
For example, let’s say you use an image of Mt. Fuji even though the text is explaining SEO measures. In this case, I’m confused as to whether I should use the Alt attribute for SEO purposes or Mt. Fuji because I’m using an image that has nothing to do with the main text.
Therefore, although it is important to describe the characteristics of the image in the Alt attribute, it is a good idea to submit images that are related to the main text.
Don’t stuff keywords
Next, it is important not to stuff the Alt attribute with keywords. Since SEO deals with keywords, many people think that stuffing them with keywords is more effective. However, only write keywords that represent the characteristics of the image. For example, let’s say you have an image that shows the top of Mt. Fuji in winter. In this case, the Alt attribute may have the following contents:
<img src=”Image URL” alt=”Autumn summit of Mt. Fuji”>
It is set to a very simple content. In the first place, the purpose of writing the Alt attribute is to display alternative text when the image is not displayed. It’s not about getting high rankings with SEO measures.
After understanding the above, make sure to write keywords using only text that expresses the characteristics of the image.
Relationship between Alt attribute description and SEO
From here, I will introduce the relationship between Alt attributes and SEO.
- Tell search engines what the image is about
- No direct SEO effect
Let’s look at each in turn.
Tell search engines what the image is about
Search engine robots (crawlers), including Google, cannot load images themselves. The content of the image is understood by referring to information such as the Alt attribute and title attribute set on the image, and the caption around the image.
Therefore, if the Alt attribute is written, it can help search engines try to understand the content of the image. As a result, your chances of ranking higher in Google image searches will increase. If you increase the number of traffic via image search, you can aim for higher rankings in natural search results.
No direct SEO effect
Alt attributes have no direct SEO effect. In other words, just because the Alt attribute is written does not directly increase the possibility of being ranked higher. On the other hand, even if the Alt attribute is not specified, it does not mean that the search ranking will drop.
If the purpose is decoration, the Alt attribute can be omitted.
Earlier, I explained that the Alt attribute has no direct SEO effect. In fact, if the image used within the text is for decorative purposes, there is no need to describe the Alt attribute. This is because the content of decorative images does not need to be conveyed to search engines, and to users, even if no alternative text is displayed, it has no bearing on the content of the main text.
However, if you are submitting
a PDF
or an image to supplement text, you will need to properly describe the Alt attribute. Therefore, you can decide whether or not to include the Alt attribute depending on what kind of image you are uploading and the purpose of that image.
What to do when the Alt attribute is not displayed
So far, we have explained the relationship between Alt attributes and SEO. However, even if you actually set the Alt attribute, there are cases where it is not displayed. If such a case occurs, it is most likely due to the Alt attribute not being properly written. In that case, please check whether the Alt attribute is correctly written in the 〇〇 section below.
<img src=”Image URL” alt=”〇〇“>
With WordPress, it will be displayed if you write it in the alternative text section.
Benefits for users of writing Alt attributes
So far, we have provided an overview of the Alt attribute. From here, we will introduce the benefits for users of writing the Alt attribute.
- You can understand the content even if the image is not displayed
- You can understand the content with the voice reading function
Let’s look at each in turn.
You can understand the content even if the image is not displayed
Even if the image is not displayed for some reason, such as due to poor communication environment on the user side, the alternative text will be displayed if the Alt attribute is specified. In other words, it is possible to complement the image content. In particular, if you want to explain the content using images, writing the Alt attribute will facilitate understanding of the content even if it is not displayed.
You can understand the content with the voice reading function
The Alt attribute is also read by the text-to-speech feature. In particular, people with visual impairments use the text-to-speech function, but the text-to-speech function cannot read the image content itself. If the Alt attribute is set, the image content will be read out in alternative text, making it easier to understand the content.
summary
In this article, we explained the Alt attribute. The Alt attribute is an attribute used to represent the content of an image. By including the Alt attribute, you can properly convey the content of the image to search engines, and at the same time, you can expect to increase the number of inflows from image searches.
Although it has no direct SEO effect, it can be said that there is no harm in setting it. Why not start by setting an Alt attribute that represents the characteristics of the image?