How to write alt text people actually benefit from

What alt text is for

A screen reader cannot look at your photo. It reads the alt text instead, in the flow of the sentence around it. So the question to ask is not what is in this picture. It is what would a reader miss if the picture vanished.

Alt text also appears when an image fails to load, which happens more often than people think on slow connections and in email clients.

It also matters more often than people expect. Images fail to load on slow connections, on metered data, in email clients that block them by default, and whenever a file is moved without its references being updated.

One sentence, in context

The best alt text is short and specific. A van outside a house is not a description. A signwritten van parked outside a job in progress tells the reader what the photo is doing on the page.

Context changes the right answer. The same headshot needs a different description on a team page than on a case study. Write for the spot the image sits in, not for the file.

A useful discipline is to write the alt text before uploading, while you still remember why you chose the photograph. Written afterwards, in a batch, it turns into description for its own sake rather than the point the image was making.

When to leave it empty on purpose

Not every image carries meaning. A decorative flourish, a background texture, a divider line, an icon that sits beside a word that already says the same thing. Those should carry empty alt.

Empty alt is not a missing description. It is an instruction to skip. Describing a swirl of brand color helps nobody, and it interrupts the sentence the reader was in the middle of.

The phrases to drop

Do not begin with image of or photo of. The software already announced that it is an image. You are spending the reader's first three words on nothing.

Do not paste the file name. Do not list your services and your city. Alt text stuffed with search terms reads as gibberish aloud, and it is the clearest possible signal that a page was written for a machine rather than a person.

• Image of, photo of, picture showing — the software already said it is an image
• The file name, which helps nobody and often reads as a serial number
• A list of services and a town, which is stuffing and sounds like it
• Click here, which describes an action rather than a picture
• Decorative, graphic, spacer — say nothing instead, with empty alt
• The same sentence on every photograph in a gallery

Before and after shots, and other pairs

Trade sites lean on paired images, and pairs are where alt text usually collapses. Two photos both described as bathroom tell a listener nothing about what changed.

Describe the state, not the subject. Cracked tiling and a stained ceiling before the work. The same wall retiled with the ceiling repainted. Now the pair means something to somebody who cannot see it.

The same logic covers product shots from several angles, progress photos through a job, and any gallery where the images are deliberately similar.

Images that carry words

A picture of text is the common failure that nobody notices. A price list saved as a graphic, an opening hours card, a quote laid over a photo. None of it can be read aloud, enlarged cleanly, or found by search.

If words matter, set them as real text on the page. If an image must carry words, the alt has to repeat them exactly. A chart needs more than a label. It needs the finding, written out in a sentence nearby.

This is also the most common accessibility fault on a site that otherwise looks careful, because the graphic was made by somebody in a design tool and nobody thought of it as text. See why a web page beats a document for the same problem at a larger size.

What a checker sees and what it cannot

A machine can tell you that an image has no alt attribute at all. That is worth catching, and every page the builder publishes is checked for it before anything publishes.

No machine can tell you whether the sentence is true. Alt text that says smiling team in office, on a photo of an empty warehouse, passes every automated test ever written. Accuracy is yours, and it is the part that matters.

Where the builder helps and where it stops

Pages here are written from a conversation about your business, and the images you supply are described in that same pass rather than left for later. The in-app assistant tells you which pictures still need a description and why.

You can rewrite any of it. You know whether the van in the photo is yours.

The judgment stays yours for a reason worth stating plainly: only you know whether the van in the photograph is yours, whether the room is the one you refitted, and whether the person in it agreed to appear.