How to Add Alt Text to Klaviyo Image Blocks

Image-sliced emails fail accessibility the boring way: every block is silent, so when images do not load the subscriber gets a stack of nothing. Alt text is not a nice-to-have for campaigns built out of pictures. It is the backup email.

What to write

Describe the offer or the thing, not the file. “30% off spring jackets, shop the sale” beats “hero_final_v3.” Skip “image of.” Screen readers already know.

Keep it short: roughly under 125 characters when you can. Match the link: if the slice goes to a product PDP, name the product. If it is a pure mood shot with no offer, say what it is without inventing a discount that is not there.

Decorative slices

Spacers, hairline dividers, and non-informative patterns should not announce themselves. Mark them decorative when the tool allows it, or leave alt empty if that is your house style. Heroes, product tiles, and CTA-as-image always get real text. Guessing wrong toward silence on a sale banner is worse than guessing wrong toward a short description.

In Klaviyo itself

1. Open the template or email in the drag-and-drop editor.
2. Click an image block.
3. Find Alt text in the block settings (wording moves between UI versions; look near the image source controls).
4. Save and move on. Yes, it is tedious. That is why you should not do this from a cold start after uploading twelve slices by hand.

Generate in bulk, then edit like a human

In Autosliced, after the cuts are locked, run one-click alt text across every slice. Then (and this is the part people skip) open the hero and any slice with a promo code or legal claim. AI is decent at “brown boots on a white background.” It is unreliable at “exactly 15% off with code SPRING15.”

I would rather ship a slightly dull correct string than a fluent wrong one. Fix the three important slices; leave the obvious product tiles if they read fine.

Logos

Usually the brand name is enough. If a text wordmark already sits next to the logo in the same slice, you may treat the mark as decorative. If the logo is the only identity on that band, give it alt.

FAQ

Does Klaviyo require alt text?

The editor will let you leave it blank. Your QA checklist and your subscribers should not. Fill content slices.

Is AI alt “good enough”?

Good enough as a first pass. Not good enough as the last pass on anything money or legal touches.