What is Alt Text?

Alt text is a short written description of an image in a web page's code, read aloud by screen readers and used by search engines to understand the image.

Many people treat alt text as a box to fill with keywords. That misses its real purpose. Alt text, short for alternative text, is a brief written description of an image, added in the image's HTML. Screen readers read it aloud for people who are blind or have low vision, and browsers show it when an image fails to load.

In simple words, alt text is how you describe a photo to someone who cannot see it. Search engines benefit from that same description, because text tells them clearly what a picture shows.

Why it matters

Alt text does two good jobs at once. First, it makes your website accessible, so more people can use it fully. In many countries, accessibility is also a legal expectation for certain kinds of websites. Second, it helps search engines understand what an image shows, which supports image search visibility and adds context to the page. It is a small but real part of on-page SEO.

Clear descriptions also give search engines and AI systems one more reliable signal about what your page covers.

Good alt text versus weak alt text

For example, imagine a jewelry store in Hyderabad with a product photo of a necklace.

Missing: no alt text at all. A screen reader may simply read out the file name, such as "IMG_4521.jpg".
Stuffed: "gold necklace, buy gold necklace online, best gold necklace Hyderabad, cheap gold necklace". This helps no one and reads poorly.
Helpful: "22 karat gold temple necklace with ruby-red stones and a Lakshmi pendant". Clear, specific and natural.

How to write it well

Describe what is actually in the image, as you would to a friend on the phone.
Keep it short, usually one sentence or less.
Include a keyword only if it fits naturally in an honest description.
Skip phrases like "image of" or "picture of", since screen readers already announce that it is an image.
For purely decorative images, such as background patterns or divider lines, use an empty alt attribute so screen readers skip them.
If an image contains important text, such as an offer on a banner, include that text in the alt text or on the page itself.
For a linked image, such as a logo that goes to the homepage, describe where the link leads.

Where it fits in your workflow

The easiest habit is to write alt text at the moment you upload an image, not months later. If you prepare product photos with a tool like our free background remover, add the description as soon as the final image goes live. And because of mobile-first indexing, make sure the alt text exists on your mobile pages too.

Simple takeaway

Write alt text for people first and search engines second. When the description truly helps a person who cannot see the image, it almost always helps your SEO as well. It takes a few seconds per image and is one of the simplest ways to improve both accessibility and user experience.