WEBSITE PLANNING

Write Image Alt Text Around the Image’s Purpose

Decide when a website image needs a description, a functional label or an empty alternative.

Ask what the image contributes

The same photograph can play different roles on different pages. On a project story it may show a particular construction detail; behind a heading it may be decorative. Write down what a reader would lose if the image were absent. That answer is a better starting point than the file name, camera settings or a list of keywords you hope to rank for.

Choose the appropriate treatment

The W3C image decision tree distinguishes informative, functional and decorative uses. An informative image needs an alternative that communicates its relevant information. For a linked image, the alternative may need to explain the link’s purpose. A purely decorative image generally uses an empty alt attribute so assistive technology can skip it. A complex chart may need a longer text explanation beyond a short alternative.

Work through three examples

A before-and-after project photograph could identify the visible change that the surrounding story discusses. A logo that is the only content of a homepage link could identify the business and destination. A decorative texture behind already visible text usually does not need a narration of its colors. These are editorial examples; the actual decision depends on the surrounding content and the implemented control.

Use an image inventory

Create columns for page, image, purpose, adjacent text, proposed alternative and reviewer. Have the content owner confirm what the image actually depicts. Do not guess a person’s name, product material or location from a photograph. Avoid repeating an entire caption when that gives no additional help. Read the page without images to see whether the key information still makes sense, and include linked images in a keyboard and screen-reader review where possible.

Keep accessibility separate from claims

Good alternatives support access to information; they do not establish that the entire site meets an accessibility standard or guarantee Google Image traffic. Publish the approved wording and retain the inventory when images change. For a website review, include representative URLs in a quote request. The W3C alt decision tree is the primary reference.