A No-Nonsense Guide to Writing Alt Text for SEO and Accessibility
What alt text is actually for, why it matters more than people think, and how to write it well in under a minute per image.
The one field everyone skips that quietly costs you traffic
Alt text is the small description attached to an image that shows up when the image fails to load, gets read aloud by screen readers, and gets scanned by search engines that can’t actually see pictures. It takes about fifteen seconds to write per image and it’s the single most skipped field on most websites, mostly because nobody explained why it matters. It matters for two very different audiences at once: real people using assistive technology, and search engines trying to understand your page.
Describe what’s actually happening in the image
Someone using a screen reader hears your alt text instead of seeing the image, so it needs to convey the same information a sighted visitor would get at a glance. “Team celebrating around a laptop after a product launch” tells a story. “Image1234” or “photo” tells them nothing at all, and it’s a surprisingly common default when alt text gets skipped or auto-generated.
Skip “image of” and “picture of”
Screen readers already announce that an image is present before reading the alt text, so opening with “image of a sunset” is redundant — just write “a sunset over the harbor at dusk.” It’s a small thing, but across a page with a dozen images, those extra words add up to real, unnecessary listening time for someone relying on audio to browse your site.
Purely decorative images can stay empty
Not every image is carrying meaning. A background texture or a decorative divider shape doesn’t need a description — leaving it blank tells assistive tools to skip right past it, which is actually the more considerate choice than forcing someone to sit through a description of an abstract pattern that adds nothing to the content.
Work in a keyword naturally, never stuff it
If an image genuinely relates to a topic your page is about, it’s fine — even helpful — to include that term naturally in the description. What doesn’t work is cramming keywords into alt text that don’t actually describe the image, which reads badly to real users and gets recognized as manipulation by search engines. Write for the person, and the SEO benefit follows honestly.
Product and detail shots deserve extra specificity
For an ecommerce listing or a portfolio piece, generic alt text like “product photo” wastes an opportunity. “Charcoal linen armchair with brass legs, front view” is genuinely useful to a screen reader user trying to decide if this is the item they want, and it gives search engines much richer context about exactly what’s being shown.
Fifteen seconds per image, done consistently, adds up
This is one of the rare wins that’s genuinely low effort and helps two completely different groups at once — the people who rely on assistive technology to use your site, and the search engines deciding whether to send you traffic. Make it part of your upload routine instead of a cleanup task you do right before launch, and it never feels like extra work.
