How to write accessible ALT text?
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Good alt text answers one question: if someone can't see this image, what do they need to know? For a product photo, that's the product name and key details. For a decorative divider or spacer, the answer is nothing. That's when you use empty alt (alt="").
Here's what makes alt text work. Be concise. Aim for under 125 characters, but don't sacrifice meaning to hit that number. Describe the function first. "Buy now button" beats "blue rectangle." Include key information that changes the meaning. A price, a product name, a call-to-action. Skip the obvious. Don't start with "Image of" or "Photo of." Your screen reader already says it's an image. For purely decorative elements. dividers, spacers, flourishes. use empty alt (alt="") so screen readers skip them. And here's what kills accessibility: omitting the alt attribute entirely. That's worse than leaving it empty.
Alt text is content strategy. You're deciding what information matters for understanding the email without seeing the image. A hero banner might need substantial alt text. An icon next to a word might just clarify function. A decorative element needs nothing.
Next step: Open one of your recent emails. Find every image. Ask yourself: if this image didn't load, would the reader still understand the message? If no, write alt text. If yes, use alt="" for decoration. Test it by previewing the email with images off in your email client.
Related: email accessibility, screen readers.
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