How to write alt text for product images

Alt text is a short written description of an image. It exists for a simple reason: some of your customers cannot see the photo. They may use a screen reader that reads the page aloud, or their image may not load on a slow connection. Alt text gives them the same information a sighted person gets from a glance. Writing it well is an act of care, and it takes only a few seconds per image.

Who actually reads alt text

Think of a person who is blind or has low vision, using software that speaks the page out loud. When the software reaches your product photo, it reads the alt text instead. If there is none, the person hears nothing, or hears a meaningless file name. They cannot tell what your product looks like.

Alt text also appears in place of an image when it fails to load. On a patchy mobile network, that happens often. A short description keeps the page useful while the picture loads or fails.

The core idea: describe what is there

Write what you would say if you were describing the photo to someone over the phone. Keep it plain and factual. Mention the product, its colour, its main feature, and what the image shows.

A weak example: "bag". Another weak one: "IMG_4821". A stronger one: "Navy cotton tote bag with long handles, laid flat, printed with a white leaf design."

Good alt text answers these questions in one short sentence:

• What is the object?
• What colour and material is it?
• What is special about this particular photo, such as worn, close-up or inside view?

Different photos, different alt text

Each image in a product gallery shows something different, so each needs its own description. Do not copy the same sentence onto all six photos. Examples for a tote bag:

• Front view: "Navy cotton tote bag with a white leaf print, laid flat."
• Close-up: "Close-up of the white leaf print on the navy canvas."
• Worn: "Person carrying the navy tote bag on one shoulder."
• Inside: "Open navy tote bag showing a plain lining and one inner pocket."

That tells a non-visual shopper what each image adds. It also helps you check your own gallery, because if two descriptions are the same, the photos probably are too.

Keep it short

A sentence or two is enough. Long paragraphs are tiring when read aloud. Aim for a clear description in fewer than around a hundred characters if you can, and do not stress about hitting a number. Put the most important information first.

Skip the words that add nothing

Do not start with "image of" or "photo of". The software already announces that it is an image. Do not stuff in lists of keywords, repeated product names or promotional words like "best" and "cheap". That makes the text hard to listen to, and it does not serve the person it is meant for. We are not making claims about search ranking here, only about being clear.

Mention readable text

If the image contains important text, such as a size chart or a label, repeat the key information in the description or on the page itself. A size chart image that is described as just "size chart" is no help to a person who cannot see it. Put the actual measurements in the product description as text. Our post on how to design a clear size chart image for mobile screens explains how to keep the chart clear.

Make it part of your upload routine

Write the alt text while you write the product title and description. It takes a minute, and doing it later usually means never. If your store tool has a field for it, fill it in for each image. If you are still organising files, how to name and organise product image files pairs well with this habit.

A quick check

Read your alt text aloud. If it makes sense to someone who cannot see the photo, it is good enough. That is the whole test.