What a Screen Reader Says When an Image Has No Description
Every image on your website carries a text description. It is invisible to most visitors and it does three jobs, and the first of them is the reason it is not optional.
What happens without one
A screen reader encountering an image with no description falls back to reading out the file name. On most platforms that is a string of characters, so a blind visitor hears a few seconds of nonsense where a description of your headshot should be.
There is a distinction worth knowing here, because it is the one people get wrong. A missing description and an empty one are not the same thing. An empty description is a deliberate statement that an image is decorative and should be skipped, and a screen reader passes over it silently. A missing one is an absence, and the software has to do something with it, so it reads the file name. For a decorative divider, empty is correct. For a headshot, neither is.
The other two jobs
The description is what appears if the image fails to load, on a slow connection or a restricted network. And it is what search engines index, which is what decides whether your headshots ever surface in image search for your own name.
So one line of text serves accessibility, resilience and search at the same time, which is an unusually good return for the effort.
Where yours come from
Every photo gets a description automatically, built from your own details rather than guessed from the picture. That is a floor: it guarantees nothing on your site is completely undescribed.
You can write your own, and it is worth doing on the images that matter. Captions on every photo covers how the caption and the description relate, since on this platform they are the same field doing both jobs.
The rule for writing one: describe what is in the frame, plainly, to somebody who cannot see it. Skip "photo of", because the context already says that. Keep it to a line, because a screen reader reads all of it before the visitor can move on.
Related: accessibility on an actor website, how your photo galleries open and how every design is checked.
