Why Image Alt Text Matters

Alt text is one of the simplest accessibility fixes available, and one of the most commonly skipped. It's a short text description attached to an image, invisible in normal browsing, but essential for a meaningful portion of your visitors.

Who actually relies on alt text

The most direct beneficiaries are people using screen readers — software that reads a webpage aloud, commonly used by people who are blind or have low vision. When a screen reader encounters an image, it reads the alt text aloud in its place. Without it, the screen reader either skips the image silently or reads out the image's filename — something like "image047.jpg" — which communicates nothing useful about what's actually there.

Alt text also matters in situations that have nothing to do with disability:

• Slow or failed connections. If an image fails to load, most browsers display the alt text in its place, so visitors on unreliable connections still get the context the image was meant to provide.
• Search engines. Image search results and general SEO both rely partly on alt text to understand what an image depicts, since search engines can't "see" an image the way a person can.

What makes good alt text

Good alt text describes the content and function of an image concisely — not every visual detail, just enough that someone who can't see the image understands what they're missing.

A few practical guidelines:

• Be specific, not generic. "Team photo" tells a screen reader user almost nothing. "Five-person marketing team standing outside the Austin office" actually communicates something.
• Skip "image of" or "picture of." Screen readers already announce that it's an image before reading the alt text — adding it yourself is redundant.
• Keep it short. A sentence or two is usually enough. Alt text isn't the place for a full paragraph description.
• Describe function for interactive images. If an image is also a clickable link (a logo linking to the homepage, an icon that opens a menu), the alt text should describe what happens when it's clicked, not just what the image looks like.
• Use an empty alt attribute for purely decorative images. A background flourish or divider graphic that adds no real information should have alt="" rather than a description — this tells screen readers to skip it entirely rather than announcing something visitors don't need to hear.

A common mistake worth avoiding

It's tempting to reuse the same alt text across many similar images — product photos on an e-commerce site, for example. But identical or near-identical alt text across dozens of images provides little real value and can make a screen reader experience feel repetitive and unhelpful. Where possible, alt text should reflect what's actually distinct about each image.

How CheckSitePulse checks this

During a crawl, CheckSitePulse identifies every image missing an alt attribute entirely, flagging each one along with the page it appears on. This won't judge the quality of alt text you've already written — that still requires a human eye — but it reliably catches the more common problem: images with no alt text at all, which is often simply an oversight from the initial page build rather than a deliberate choice.

Alt text is a small addition per image, but across a whole website it adds up to a meaningfully more usable experience for a real segment of your visitors — and it's one of the more straightforward accessibility fixes to work through once you know where the gaps are.