Alt text
If you’ve ever popped an image into a blog post or uploaded a chart to a report in your CMS, chances are you’ve been prompted to “add alt text.” It might seem like an optional step, one of those accessibility boxes to tick, but alt text plays a more important role than many realise.
Alt text, short for “alternative text,” is a written description of an image designed to be read by screen readers for people with visual impairments. Its main job is to make visual content understandable to those who can’t see it. However, alt text also carries weight in several other key areas, especially regarding SEO and content performance.
Suppose you’re a B2B SaaS company publishing a blog post about marketing automation trends. You include an image of a dashboard showing campaign analytics. A good alt text for that image might be: “Marketing automation dashboard showing email open rates and click-through data.”
There’s a bit of a misconception that alt text is just a chance to sprinkle in keywords, but that’s not its real purpose. Yes, including relevant keywords naturally can support SEO, but keyword stuffing (e.g., “marketing dashboard email campaign strategy SaaS B2B”) makes for bad accessibility and a clunky user experience. Aim for helpful, human sentences that give context.
Here are a few quick tips for writing effective alt text:
- Describe what you see, focusing on the function or meaning of the image.
- Keep it brief: around 100 characters is a good guideline.
- Include text in the description if text appears in the image (like in a screenshot or infographic).
- Avoid phrases like “image of” or “picture of”; screen readers already announce that it’s an image.
Alt text matters because inclusive design matters. Not every visitor to your site will experience it the same way, but that shouldn’t stand in the way of understanding your message. And with increasingly stricter accessibility laws and evolving search engine algorithms, properly written alt text is the right thing to do and a smart move.