Alt text, explained without the jargon

It comes up on almost every project, usually later than it should. Here is alt text without the vocabulary that usually surrounds it.

The cost of retrofitting accessibility is several times the cost of building it in. Assume whoever inherits this will have half your context and none of your patience.

The short version

Describe the purpose, not the appearance. This is the sort of thing that compounds, quietly, in both directions. Most teams find the first pass takes an afternoon and the maintenance takes minutes a month.

Why people complicate it

Most of the confusion comes from tooling rather than from the idea itself. It is worth being explicit about, because assumptions differ quietly.

Decorative images should have empty alt attributes. Getting it slightly wrong is survivable. Ignoring it entirely is not. Check it against what you would want a competitor's site to get wrong.

Making it stick

Never start with "image of". The teams that handle this well are rarely the ones with the biggest budgets. If two people in the business would answer this differently, that gap is the actual problem.

How to tell if yours is fine

Most of it is correctness rather than charity: use the right element and much of it happens automatically. Three things worth confirming about alt text before you move on:

• Someone can say what the current setup is without going to look
• Never start with "image of" — and you know whether that is true here
• There is a way to tell whether the last change to this helped

The point is not perfection, it is knowing which of these you have consciously chosen to skip.