Image alt text, also known as 'alt tags' or 'alt descriptions,' is an important aspect of SEO as it provides search engines with a description of the image content. It is also crucial for website accessibility because it describes images to visually impaired users using screen readers.
There isn't a specific length limit set by search engines like Google for image alt text, however, best practices suggest keeping your alt text to around 125 characters or less. This is mainly because screen reading tools typically stop reading alt text after approximately 125 characters.
Here's an example of how to add alt text to an image in HTML:
In this code snippet,
"Description of the image under 125 characters" is the alt text. Make sure this text accurately describes the image content, contains your keyword (if applicable), and stays within the recommended character limit.
Remember, the primary purpose of alt text is to improve accessibility and provide better user experience. Avoid stuffing keywords where they don't naturally belong, as this can harm the user experience and potentially cause search engines to perceive your site as spammy.