Alt text (short for alternative text) is the written description applied to an image via the HTML alt attribute. When an image can’t be displayed — due to a slow connection, a broken image URL, or a user’s browser settings — the alt text appears in its place. For users who are visually impaired and rely on screen readers, alt text is read aloud to describe what the image shows. For search engines, alt text is one of the primary signals used to understand an image’s content and context.

Alt text sits at the intersection of accessibility and SEO. Well-written alt text makes a website more inclusive for users with visual impairments, satisfies legal accessibility standards, and helps search engines index your visual content accurately. Neglecting it leaves both groups — human users and search engines — without context they need. In WordPress, alt text is added directly in the Media Library when uploading images, and it applies everywhere that image is used across the site.

[Image: Side-by-side comparison of an image in a browser showing it normally, versus an image with a broken link showing alt text displayed in its place]

How Alt Text Works

In HTML, alt text is placed within the img tag using the alt attribute:

<!-- No alt text — poor for accessibility and SEO -->
<img src="team-photo.jpg">

<!-- Generic alt text — marginally better, still unhelpful -->
<img src="team-photo.jpg" alt="photo">

<!-- Descriptive alt text — correct approach -->
<img src="team-photo.jpg" alt="CyberOptik web design team gathered around a conference table reviewing a website project">

For decorative images that convey no meaningful content — dividers, background textures, purely aesthetic icons — the correct approach is an empty alt attribute (alt=""). This signals to screen readers that the image is decorative and can be safely ignored, rather than reading a filename or placeholder text to the user.

According to Google’s image SEO documentation, alt text should be “useful, information-rich content that uses keywords appropriately and is in context of the content of the page.” The recommended length is 5–15 words or under 125 characters — concise enough for screen readers, specific enough to be meaningful.

Purpose & Benefits

1. Accessibility for Users with Visual Impairments

Screen readers used by blind and low-vision users rely on alt text to narrate images. Without it, the screen reader either skips the image silently or reads the filename (often something like “IMG_4582.jpg”) — neither of which communicates anything useful. Under WCAG 2.2, providing alt text for meaningful images is a Level A accessibility requirement — the minimum baseline. Sites that fail accessibility standards face both a worse user experience and potential legal exposure under ADA guidelines. Our web accessibility services include comprehensive alt text auditing.

2. Search Engine Indexing of Images

Search engines can’t “see” images the way humans do — they read the alt attribute to understand what an image depicts. Descriptive alt text helps Google and other search engines correctly categorize your images, improving their chances of appearing in Google Images and visual search tools like Google Lens. For businesses where images directly represent products, portfolios, or services, this is an additional organic traffic channel worth optimizing. Alt text also reinforces the topical relevance of the page it’s on.

3. Displaying Content When Images Fail

When an image fails to load — broken link, slow network, corporate firewalls blocking certain file types — the alt text renders in its place. This prevents a confusing blank space or broken image icon and ensures the core information conveyed by the image is still accessible to the visitor. In email marketing, where many email clients block images by default, alt text is the text recipients see before deciding whether to load images.

Examples

1. Product Image on an eCommerce Site

A WooCommerce store sells handmade ceramic mugs. A product image alt text of "alt" or "mug" tells search engines almost nothing. A better approach:

  • Poor: alt="mug"
  • Better: alt="blue ceramic mug"
  • Best: alt="Handmade speckled blue ceramic mug with wooden handle, 12 oz"

The specific description helps Google Images index the product correctly, supports visual search queries, and describes the product clearly to a screen reader user.

2. Team Photo on an About Page

A company’s About page includes a group photo of the team.

  • Poor: alt="IMG_2301.jpg" (auto-filled from filename)
  • Better: alt="Company team photo"
  • Best: alt="Five-person marketing team standing in front of the company office entrance"

The descriptive version tells a screen reader user who is in the photo and where it was taken — the same information a sighted user would glean from looking at the image.

3. Decorative Divider Image

An ornamental divider graphic between sections has no informational value.

<!-- Correct: Empty alt for decorative images -->
<img src="divider-pattern.png" alt="">

The empty alt="" tells screen readers to skip this image entirely. If it were omitted, some screen readers would read the filename instead — which is worse than nothing.

Common Mistakes to Avoid

  • Starting with “Image of…” or “Photo of…” — Screen readers already announce that content is an image. Writing “Image of a golden retriever” is redundant. Write “Golden retriever sitting in a park” — describe the subject directly.
  • Keyword stuffing alt text — Using alt text as a place to cram keywords (“web design agency web design company web development WordPress website”) is a spammy practice that can harm rather than help your SEO and creates a terrible experience for screen reader users.
  • Using the same alt text for multiple images — Every image shows something different and deserves a unique description. Duplicate alt text looks like low-effort optimization and fails to differentiate visually distinct images.
  • Leaving alt text blank by default — WordPress often pre-populates alt text with the filename if nothing is entered. Filenames like “DSC_4719” or “image-1” are meaningless. Always add intentional alt text when uploading to the Media Library.

Best Practices

1. Write for the Person Who Can’t See the Image

The best alt text is written as if you’re describing the image to someone over the phone. What would they need to know? What does the image communicate? Focus on the information conveyed, not just what the image looks like. For an infographic showing sales data, the alt text should describe what the data shows, not just “sales infographic.” This approach naturally produces alt text that serves both accessibility and SEO.

2. Keep It Concise but Specific

Aim for 5–15 words, under 125 characters. Screen readers typically cut off alt text beyond 125 characters, and longer descriptions become harder to parse as spoken audio. If an image is complex — a chart, infographic, or diagram — use concise alt text to describe its purpose, then provide the detailed content in the surrounding text or a caption. For example: alt="Bar chart showing quarterly revenue growth 2023–2025" followed by the actual data in the page text.

3. Integrate Alt Text Into Your Content Workflow

Alt text shouldn’t be an afterthought added during a site audit. Build it into your content workflow — anyone uploading images to the Media Library should add alt text at upload time. In WordPress, the alt text field appears directly in the image upload dialog. Making this part of your standard process eliminates the much larger task of retroactively updating hundreds of images. Tools like accessibility audits and Google’s Lighthouse can identify images missing alt text across your site.

Frequently Asked Questions

Does alt text directly improve my Google rankings?

Alt text isn’t a primary ranking factor for standard web pages, but it contributes meaningfully to on-page SEO. It helps Google understand your images, which supports your page’s topical relevance and enables ranking in Google Images — a separate traffic source. For image-heavy industries (retail, food, design, real estate), Google Images traffic can be substantial.

What should I do for decorative images?

Use an empty alt attribute: alt="". This is the correct HTML practice for images that are purely decorative — icons, background patterns, spacers. It signals to screen readers to skip the image. Don’t omit the attribute entirely — an omitted alt attribute can cause screen readers to read the image URL or filename, which is worse than nothing.

How do I add alt text in WordPress?

In WordPress, you can add alt text in two places: when uploading an image directly (the “Alternative Text” field in the attachment details panel), or when inserting an image into the Block Editor (the Alt Text field in the right-hand block settings panel). Alt text added in the Media Library applies to that image file across the site by default, though you can override it per instance in the editor.

Does every image need alt text?

Every meaningful image needs descriptive alt text. Decorative images (visual embellishments with no informational content) should have empty alt attributes (alt=""). The distinction matters: meaningful images include product photos, team photos, infographics, screenshots, and charts. Decorative images include purely aesthetic dividers, background patterns, and redundant visual elements.

How does alt text help with ADA compliance?

The Americans with Disabilities Act (ADA), as interpreted through WCAG guidelines, requires that digital content be accessible to people with disabilities. WCAG 2.2 Level A (the minimum standard) requires that all non-text content have a text alternative. Missing or meaningless alt text is one of the most common accessibility failures found in site audits — and one of the most straightforward to correct.

Related Glossary Terms

How CyberOptik Can Help

Alt text is one of those details that’s easy to overlook and adds up to a meaningful gap over time — in both accessibility and SEO. Our team includes alt text review in site audits and makes it part of every web design and development project we deliver. Whether you need an accessibility audit to find gaps, a content workflow that builds alt text into your process, or a full SEO review of your image optimization, we can help. See our web design services or learn about our SEO services. Contact us to start a conversation.