Alt Text Examples for SEO: Good and Bad Explained

This guide gives you practical alt text examples for SEO, good and bad side by side, along with what Google actually recommends and a formula you can use for every image on your site. I write and fix alt text on most of my on-page projects, so the examples come from the types of images real businesses publish.

What does good alt text look like?

Good alt text is a short, specific description of what the image shows and why it is on the page, written so someone who cannot see it gets the same information. Google’s own example is alt=”Dalmatian puppy playing fetch”.

Google’s image SEO best practices call alt text the most important attribute for giving Google more information about an image. The same page shows three versions for one photo: missing alt text (bad), a stuffed list like “puppy dog baby dog pup pups puppies doggies” (bad), and “Dalmatian puppy playing fetch” (best). That one example teaches most of what you need.

Google’s technical writing course on writing helpful alt text adds useful rules: use a short phrase or one or two sentences, do not add words like “Image of” or “Photo of”, explain the image in the context of the surrounding text, and use an empty alt attribute for decorative images.

My formula is simple: subject + key detail + context. Who or what is in the image, what is important about it, and why it matters on this page.

What are good and bad alt text examples?

The clearest way to learn alt text is to compare weak versions with improved ones for the same image. This table covers the image types I see most on business sites.

Notice two patterns. Good alt text is specific (three seater, oak legs, Leeds office), and it changes with the job of the image. A linked logo describes where the link goes, not what the logo looks like.

How long should alt text be for SEO?

Alt text should be as long as it needs to be to describe the image, which for most images means a short phrase or one or two sentences. Google does not set a character limit.

The Google technical writing guidance says to use a short phrase or one or two sentences and explains that long descriptions slow down screen reader users. In practice, most of the alt text I write is between about 5 and 15 words. If an image needs more, such as a complex chart, give it a short alt text and explain the details in the body text, a caption or a linked page.

A few length rules I use:

• Product photos: name, colour, material and angle if there are several photos.
• People: who they are only if it matters to the page, plus what they are doing.
• Charts and diagrams: the main takeaway, not every number.
• Screenshots: what part of the interface is shown and what is selected.

Should alt text include keywords?

Alt text should include a keyword only when the keyword honestly describes the image. Forcing keywords into alt text does not help and can count as keyword stuffing.

Google explicitly warns against filling alt attributes with keywords, because it creates a negative user experience and may cause the site to be seen as spam. On a page about “emergency plumber in Leeds”, a photo of a technician fixing a boiler can honestly say “Plumber repairing a boiler during an emergency call out in Leeds” if that is what the photo shows. It should not say “emergency plumber Leeds best emergency plumber cheap”.

A good test: read the alt text aloud as if describing the photo to someone on the phone. If it sounds natural, it is fine. If it sounds like a list, rewrite it.

Do decorative images need alt text?

Decorative images need an alt attribute, but it should be empty (alt=””), so screen readers skip them. Leaving the alt attribute out entirely is different: some screen readers then read the filename aloud.

An image is decorative when removing it would not change the meaning of the page: background patterns, dividers, purely visual flourishes, or an icon next to text that already says the same thing. When in doubt, ask whether a reader who cannot see the image would miss any information. If not, use empty alt.

In WordPress, leaving the alt field blank in the block editor typically outputs alt=”” for that image. Check your theme and page builder, as some output no alt attribute at all, which is a quick fix in the template. You can spot missing alt attributes across a page with a crawler or with the browser tools listed on my free SEO tools page.

How do you rewrite alt text for a whole page?

Alt text is one part of image and media optimization, which I cover in my content and media SEO service and check on every on-page SEO project. If terms like alt attribute or keyword stuffing are new to you, the SEO glossary explains them in plain words.

Frequently asked questions