Alt text best practices for microsite accessibility

Alt text is one of the most impactful accessibility features you can implement in a microsite. It makes your content usable by people who rely on screen readers, improves your SEO, and ensures your message reaches the widest possible audience.

Despite its importance, alt text is often overlooked or written poorly. This guide covers what you need to know to write effective alt text for every image in your microsite.

What is alt text and why does it matter for microsites?

Alt text (short for alternative text) is a written description of an image embedded in the HTML code. When a screen reader encounters an image, it reads the alt text aloud so the user understands what the image shows. When an image fails to load, the alt text appears in its place.

For microsites, alt text matters because:

• Accessibility: An estimated 2.2 billion people worldwide have some form of visual impairment. Alt text ensures your microsite content is accessible to all users.
• SEO: Search engines use alt text to understand and rank images. Well-written alt text can help your microsite images appear in image search results.
• User experience: When images don’t load — which happens on slow connections or in email clients — alt text provides context so the message isn’t lost.

How to write effective alt text for microsite images

Describe the content, not the file

Good alt text describes what the image shows in the context of your microsite. Instead of writing “image013.jpg” or “photo,” describe the relevant content.

Instead of: “Sales chart”
Write: “Bar chart showing 60 percent increase in proposal engagement after switching to interactive microsites”

Keep it concise but descriptive

Alt text should be long enough to convey the essential information but short enough to be useful. Aim for 125 characters or fewer for most images. Complex images like charts may need longer descriptions.

Instead of: “A person”
Write: “Sales director presenting a microsite proposal on a tablet to a client in a conference room”

Include keywords naturally

If the image relates to your content topic and a keyword fits naturally, include it. But never force keywords. Alt text written for SEO at the expense of accessibility helps no one.

Natural: “Marketing team reviewing an ABM microsite campaign dashboard”
Forced: “ABM marketing microsite campaign team review dashboard analytics tools”

Mark decorative images appropriately

Not every image needs descriptive alt text. Decorative images — background textures, ornamental dividers, decorative icons — should be marked with empty alt text (alt="") so screen readers skip them entirely.

Common alt text mistakes to avoid

Mistake 1: Leaving alt text empty on meaningful images

An empty alt attribute tells screen readers to skip the image. If the image conveys information, that information is lost to users who can’t see it. Every content image needs descriptive alt text.

Mistake 2: Using “image of” or “photo of”

Screen readers already announce that an element is an image. Starting your alt text with “image of” or “photo of” is redundant.

Instead of: “Image of a team working on a microsite”
Write: “Team collaborating on a microsite layout in a design review session”

Mistake 3: Keyword stuffing

Filling alt text with keywords makes it unusable for screen readers and can harm your SEO. Write for people first, search engines second.

Mistake 4: Being too vague

Alt text like “meeting” or “office” doesn’t tell the user anything useful. Be specific about what the image shows and why it’s relevant to the surrounding content.

Alt text and SEO: understanding the connection

Google uses alt text as one of many signals to understand image content. Well-written alt text can help your images rank in Google Image Search, which can drive additional traffic to your microsite.

However, alt text is primarily an accessibility feature. The SEO benefit is a secondary outcome of doing the right thing for your users. Write alt text that serves accessibility needs first, and the SEO value will follow naturally.

Implementing alt text at scale in your microsite program

When you’re managing multiple microsites with dozens or hundreds of images, writing alt text for every image can feel overwhelming. Here’s a practical workflow:

1. Make it part of the template. When you create microsite templates, include placeholder alt text that content creators can customize. This ensures alt text isn’t forgotten.

2. Set guidelines for your team. Share a simple rule: if an image conveys information, it needs descriptive alt text. If it’s purely decorative, mark it as decorative.

3. Include alt text in your review process. Before publishing any microsite, verify that all content images have meaningful alt text and that decorative images are properly marked.

4. Use your platform’s tools. Zoomforth includes dedicated alt text fields in the media library and site editor, making it easy to add and manage alt text for every image in your microsite without writing HTML.

Ready to build accessible microsites? Request a demo to see how Zoomforth supports accessibility features.