Find every image missing alt text in Storyblok

Every Storyblok space we take over has images without alt text. Not a few, usually a lot. Nobody decided to skip it, it just never had a moment: images go in while the pages are being built, the upload doesn't ask, and once the site is live nobody opens every story to check.

Why it's worth fixing

• People using screen readers. Without alt text, an image is either skipped or read out as its filename, which isn't helpful to anyone.
• The law, increasingly. The European Accessibility Act has applied since June 2025, and accessibility audits check alt text first, because it's the easiest thing to spot.
• Search. Alt text is how search engines and AI tools know what an image shows. It's what gets your images into image search, and what an AI summary of your page has to go on.

Where alt text goes missing in Storyblok

• Asset fields. Each image you pick has its own alt text in the story, filled in or not.
• Multi-asset fields. Galleries and sliders. Every image in them has its own alt text, and it's easy to fill in the first and forget the rest.
• Images inside rich text. A rich text field can hold images too, each with its own alt text. They're easy to miss, because they don't look like a field at all.

The asset library isn't the source

When you pick an image in a story, Storyblok copies its alt text from the asset library into that story. After that they're separate. Storyblok's own team describes the library's alt text as “only a template”.

So filling in alt text in the asset library helps the next time someone picks that image, but stories that already use it keep their old, often empty, alt text. To fix a story, edit the alt text on the image in that story, or pick the image again.

And one more catch: an empty alt text looks the same whether someone forgot it or left it empty on purpose. A background texture should have empty alt text, but in Storyblok it looks exactly like a mistake.

See every image without alt text, with Cojack

We built Cojack because there was no way to answer “which images on this site have no alt text?” without opening every story. It reads your whole space and checks every image in every story.

1. Paste your site's URL into Cojack
2. On the overview, the pages with images missing alt text check shows how many pages are affected and how many images in all
3. Open Assets and click Missing alt text to see every image, with the stories it's in. Sort by Most missing alt to put the images missing it in the most places first
4. Open a story to see its images, and use Only without alt to see just the ones to fix

If you add a personal access token, Cojack also reads your asset library. Then Alt only in library shows images whose alt text is in the library but never reached the story, so you know exactly which ones to update.

Writing alt text that's actually useful

Write what the image is doing on the page, as you'd describe it to someone on the phone. A sentence is usually plenty.

• Skip “image of” and “photo of”. Screen readers already say it's an image.
• Say what matters here. A product shot on a shop page needs the product and colour, the same shot in a blog header might just need the mood.
• Include any text in the image. If a graphic says “50% off this week”, the alt text should too.
• Linked images describe where they go. A logo that links home is “Undefined, home”, not “logo”.
• No keyword stuffing. It helps nobody, search engines included.

A few before and afters:

• “hero-final-v3.jpg” → “A cyclist riding along the coast at sunset”
• “banner” → “50% off all winter coats, this week only”
• “team photo, team, about us, agency team” → “The Undefined team at the 2024 offsite”

How we set up new Storyblok projects so it doesn't happen

• Alt text at upload. The one rule we give editors: write the alt text in the asset library when you upload, before the image goes in a story. Storyblok copies it in when the image is picked.
• Decorative images out of asset fields. If an image shouldn't be read out, it's part of the component's styling, not an asset field that looks like it's missing something.
• A check before launch. We run the site through Cojack before it goes live, and missing alt text is on the list.