Alt Text

SEO

Also: Alternative Text · Alt Attribute · Alt Tag

What it isWritten description of an image

Who reads itScreen readers and search bots

Watch forKeyword stuffing gets penalised

Pairs withImage optimisation

Quick definition

Alt text, short for alternative text, is a written description attached to an image in a page's code. It's read aloud by screen readers for vision-impaired users and read by search engines that can't interpret images the way humans do. It also displays if the image fails to load.

How it varies across Australia

Missing or empty alt text is one of the most common technical SEO gaps we see across Australian sites, particularly on ecommerce product pages with hundreds of images added in bulk. The gap tends to widen the larger the catalogue, since alt text rarely scales with product volume unless it's templated.

See digital maturity benchmarks across Australian industries →

What it actually means

Alt text exists because not everyone experiences a page visually. A screen reader hits an image and needs something to say out loud. Google's crawler hits an image and needs something to index, because it can't reliably know what's in a photo without help. Alt text answers both.

The accessibility purpose came first and still matters most. Under the Web Content Accessibility Guidelines (WCAG), meaningful images need alt text for a site to be considered accessible. That's not a nice-to-have. It's the difference between a vision-impaired customer completing a purchase and abandoning your site entirely.

The SEO benefit is real but secondary. Google uses alt text as one signal among many for image search rankings and general page understanding. It's not a loophole for cramming keywords into invisible text. Google's systems are well past falling for that, and stuffing alt text with search terms tends to look exactly like what it is: manipulation, not description.

Good alt text describes what a sighted user would actually notice. A photo of a red leather sofa gets 'red leather three-seater sofa in a living room', not 'sofa couch furniture lounge buy cheap sofa australia'.

Alt text isn't a ranking trick. It's the difference between a blind user knowing what's on your page and being locked out of it.

How it shows up

Alt text shows up in an accessibility audit as a pass or fail against WCAG criteria. It shows up in Search Console and third-party crawlers as a list of images missing the attribute entirely. It shows up in Google Images as the reason a product photo does or doesn't surface for a relevant search. And it shows up, silently, every time a screen reader user lands on a product page and either gets a useful description or hears nothing at all.

The Australian context

Disability discrimination law in Australia treats website accessibility as a live legal risk, not a theoretical one. The Disability Discrimination Act has been used successfully against Australian organisations for inaccessible digital services. Alt text is one of the cheapest, fastest fixes on the accessibility checklist compared to structural issues like colour contrast or keyboard navigation, which makes ignoring it a harder position to defend if a complaint ever lands.

Where people get this wrong

Stuffing alt text with keywords instead of describing the image.Google's systems can tell the difference between a description and a keyword list. It reads as manipulation and can drag down trust signals on the page, not just the image.

Leaving alt text blank across an entire product catalogue.Every blank image is a gap in your site's accessibility and a missed chance for image search visibility. It compounds fast on ecommerce sites with large catalogues.

Writing identical alt text for every variant of a product.If ten colour variants of the same shoe all say 'running shoe', screen reader users can't tell them apart and search engines can't differentiate the pages either.

Common questions

Does alt text help with SEO rankings?

It helps mainly with image search visibility and general page understanding, not with pushing a page higher in standard search results. Treat it as an accessibility requirement first. Any SEO benefit is a side effect of doing it properly, not the main reason to bother.

How long should alt text be?

Long enough to describe what matters, usually under 125 characters. Screen readers often cut off longer descriptions. Describe the image's purpose on the page, not every visual detail. A product photo needs the product described, not the studio lighting.

Do decorative images need alt text?

Purely decorative images (a background pattern with no informational content) should have an empty alt attribute, written as alt="", so screen readers skip over them. Adding a description to a decorative image just adds noise for someone using a screen reader.

Can I automate alt text with AI?

AI-generated alt text is a reasonable starting point for large catalogues where manual writing isn't realistic, but it should be reviewed, not trusted blindly. AI tools still misread product colours, count objects wrong and miss context a human would catch instantly.

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About New Rebellion

New Rebellion is a marketing intelligence consultancy. We build tools, score Australian businesses on how their marketing actually performs, and publish Debrief every day. This dictionary is part of how we work in the open.

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