Understanding Alt Text: Meaning, Importance, and Writing tips
Images play a vital role in enhancing the visual appeal and storytelling power of any website or digital content. However, not every user experiences content in the same way. That’s where alt text, or alternative text, comes in. Alt text is a written description of an image that appears in place of the image if it fails to load and is also read aloud by screen readers to assist visually impaired users.
Alt text is more than just a technical detail—it’s a foundational element of web accessibility. For users who rely on screen readers, alt text provides essential context and ensures they can fully understand and navigate a website. Inaccessible images without descriptions can leave users missing out on key information, making alt text a must-have for inclusive design.
But accessibility isn’t the only benefit. Alt text also plays a key role in image SEO. Search engines like Google rely on alt text to interpret what an image shows, which helps them decide when and where to display that image in search results. Properly written alt text can improve your visibility in Google Image Search, boost overall page relevance, and increase organic traffic.
In this guide, we’ll explore the essentials of alt text: what it is, why it matters, how to write it effectively, and best practices to follow. Whether you’re a content creator, web designer, marketer, or SEO professional, this post will help you understand how to use alt text not only to make your website more accessible but also to enhance its search performance.
Let’s dive in and learn how a few carefully chosen words can make a big difference—for users and search engines alike.
Why Alt Text Matters
Alt text is essential for both accessibility and SEO, making it a critical part of any website’s content strategy.
First and foremost, alt text improves accessibility for users with visual impairments. Many people rely on screen readers or other assistive technologies to browse the web. When an image is encountered, the screen reader reads the alt text aloud, providing a description of the image’s content. Without alt text, these users miss important information, which can hinder their understanding of the page or prevent them from fully engaging with the content. Alt text ensures that websites are inclusive, compliant with accessibility standards such as the Web Content Accessibility Guidelines (WCAG), and provide an equitable browsing experience for all users.
Beyond accessibility, alt text plays a vital role in search engine optimization (SEO). Search engines cannot “see” images the way humans do; instead, they rely on alt text to understand what the image depicts. Properly written alt text helps search engines index images accurately, making it more likely for your images to appear in relevant image search results. This can drive additional organic traffic to your site. Furthermore, alt text contributes to the overall SEO health of a page, supporting keyword relevance and content context.
In summary, alt text bridges the gap between visual content and both users who rely on assistive tools and search engines seeking to understand your content. Ignoring alt text means missing out on better accessibility and valuable SEO opportunities, so it’s a small but powerful way to enhance your site’s effectiveness.
How to Add Alt Text
Adding alt text to images is straightforward, whether you’re managing a website or posting on social media. Here’s how to do it efficiently.
On Websites (Using a CMS)
If you use a Content Management System (CMS) like WordPress, Shopify, or Wix, you typically have two ways to add alt text:
- Via HTML code: When editing your site’s code, you add alt text inside the image tag, like this:
<img src=”image.jpg” alt=”Your descriptive alt text here”> - Via CMS interface: Most CMS platforms offer a dedicated field for alt text in the image settings or media library. For example, in WordPress, when you upload an image, there’s an “Alternative Text” box on the right sidebar where you enter your description. This method requires no coding and is user-friendly.
On Social Media Platforms
Many social media sites now support alt text to improve accessibility:
- LinkedIn: When uploading an image, click the “Add alt text” option. Enter a concise, descriptive text that explains the image.
- Facebook, Twitter, and Instagram: These platforms offer similar options during the upload process, often labeled as “Alt Text” or “Accessibility” settings.
By consistently adding alt text across your website and social media channels, you ensure your content is accessible and SEO-friendly, broadening your reach and improving user experience.
6 Best Practices for Writing Alt Text
Writing effective alt text isn’t just about adding any description—it’s about crafting meaningful, clear, and concise text that benefits both users and search engines. Here are six best practices to help you write alt text that really works.
1. Be Descriptive
Your alt text should clearly describe what the image shows. Aim to provide enough detail so users who can’t see the image understand its content and context. For example, instead of “product photo,” describe the product specifically, such as “red leather wallet with zippered compartment.” This approach helps users visualize the image and makes your content more accessible.
However, avoid redundancy. Don’t use phrases like “image of” or “photo of,” since screen readers already announce the presence of an image. Also, don’t duplicate information already present in captions or surrounding text. The goal is to add unique, useful context without unnecessary repetition.
Example: On a product category page, the alt text might be “assorted bath bombs in vibrant colors,” but on an individual product page, it should be more specific, like “lavender-scented purple bath bomb with flower petals.”
2. Keep It Short
Keep your alt text under 125 characters. Screen readers tend to cut off or speed through longer descriptions, which can confuse users. Concise alt text ensures users quickly get the essential information without being overwhelmed.
3. Include Relevant Keywords
Incorporating relevant keywords naturally can help your images rank better in search results. For example, if your image is about a “ceramic coffee mug,” including that phrase in the alt text helps search engines understand the image’s topic.
However, avoid keyword stuffing—the practice of cramming keywords unnaturally into alt text. Keyword stuffing harms readability and accessibility, and search engines may penalize your site for it.
4. Skip Decorative Images
Not all images need alt text. Decorative images, which serve purely visual or stylistic purposes (like background patterns or icons), should use a null alt attribute (alt=””). This tells screen readers to skip these images, preventing unnecessary noise and improving user experience.
Failing to do this may cause screen readers to read the image file name or irrelevant data, which can confuse users.
5. Localize Alt Text
If your site serves users from different regions or languages, localize your alt text to match the audience’s cultural and linguistic context. For instance, a soccer jersey might use “soccer jersey” for American English but “football jersey” for British English users.
Tailoring alt text not only enhances clarity but also improves SEO by using region-specific keywords.
6. Audit Alt Text Regularly
Alt text should never be “set and forget.” Regularly audit your media library to identify missing or weak alt text. Tools like your CMS media manager or SEO plugins can help find images lacking descriptions.
Keep alt text updated as your content evolves. For example, if you change an image or update page content, revise the alt text accordingly to maintain accuracy and relevance.
By following these best practices, you can ensure your alt text is accessible, SEO-friendly, and genuinely useful to all users. Writing thoughtful alt text is a simple step with a big impact—both for your audience and your website’s search performance.
Bonus: Use AI to Speed Up Alt Text Creation
Writing alt text manually for dozens or even hundreds of images can be time-consuming. Thankfully, AI tools like ChatGPT or Claude can help streamline the process without sacrificing quality.
To begin, simply upload or describe your image to an AI writing assistant. Then, provide a clear, detailed prompt that includes relevant information such as image context, target keywords, and preferred character limits. For best results, specify that the alt text should be descriptive, under 125 characters, and avoid keyword stuffing.
Example prompt:
“Generate 3-5 alt text options for an image of a woman hiking on a forest trail during fall. Include the keyword ‘autumn hike’ and keep each description under 125 characters.”
Once the AI generates the suggestions, your next step is reviewing them for accuracy and tone. Ask yourself:
- Does the description clearly represent the image?
- Is it concise and accessible?
- Is the keyword used naturally?
If needed, you can tweak the text to better match your voice, your audience, or your brand guidelines.
AI is especially helpful when:
- Writing alt text at scale (e.g., for product catalogs or blog libraries)
- Brainstorming multiple variations quickly
- Localizing content for different languages or audiences
While AI can’t fully replace human judgment, it can be a powerful support tool to save time, maintain quality, and ensure consistent alt text across your site.
Example AI-Generated Alt Texts
Here’s an example of using AI to generate alt text for a specific image:
Image: A double rainbow stretching over a green field under a cloudy sky.
AI Prompt:
“Write multiple alt text options for this image. Each should be under 125 characters, include the keyword ‘double rainbow,’ and describe the key visual elements.”
Generated Alt Text Options:
- Double rainbow arches over a green field beneath a cloudy afternoon sky.
- A vivid double rainbow appears above a wide grassy field after rainfall.
- Cloudy sky with a double rainbow stretching over a sunlit green meadow.
- Double rainbow spans the horizon above farmland and scattered wild grasses.
- Bright double rainbow forms above an open field on a stormy spring day.
These results offer clear, descriptive summaries that are easy to understand and meet screen reader standards. The keyword “double rainbow” is naturally integrated, and none of the entries exceed the character limit.
If you wanted to refine one, you might simplify or remove redundant terms. For example, if your site already mentions “stormy spring day,” you could cut that phrase to keep the alt text more concise.
Using AI in this way saves time and ensures that your alt text is consistently written, SEO-aligned, and user-friendly.
How to Check for Missing Alt Text
Even if you write great alt text, it won’t help if it’s missing from your images. That’s why it’s crucial to regularly audit your website for missing or incomplete alt attributes. Doing so ensures your content remains accessible, SEO-friendly, and compliant with web standards.
1. Use Your CMS or Browser Inspection Tools
If you manage your website using a CMS like WordPress, Wix, or Shopify, start by checking the Media Library or image blocks within your content editor. These platforms often display whether an image has alt text attached. Clicking into each image allows you to view, edit, or add missing alt descriptions directly.
For a more technical approach, use your browser’s “Inspect” tool (right-click > Inspect) to view the HTML of any image on your page. Check for the alt=”” attribute in each <img> tag:
- If the alt attribute is missing entirely, that image is not optimized or accessible.
- If it’s present but empty, it’s treated as decorative and skipped by screen readers.
2. Use SEO Audit Tools or Plugins
There are several tools available to help automate this process:
- WordPress Plugins like Yoast SEO, Rank Math, or Accessibility Checker can scan for missing or weak alt text.
- For broader site-wide checks, tools like Ahrefs, Screaming Frog SEO Spider, or Sitebulb can crawl your site and generate reports on missing alt attributes.
- Some platforms offer visual dashboards showing which pages or images need attention.
These tools can save hours of manual review and help ensure no image is overlooked.
3. Review Regularly for Accessibility & SEO
Alt text shouldn’t be a one-time task. Set a schedule to review your images quarterly or alongside major content updates. This ensures all new images are properly tagged and older content stays compliant with evolving standards.
Regular audits keep your site accessible, optimized, and user-friendly—key elements of both ethical web design and strong SEO performance.
Conclusion
Alt text may seem like a small detail, but it plays a big role in both accessibility and SEO. For users with visual impairments, alt text is essential—it allows screen readers to describe images, ensuring that everyone can fully access and understand your content. From an SEO perspective, alt text helps search engines interpret your images, which can improve rankings in image search and contribute to higher overall page visibility.
Whether you run a blog, manage an eCommerce store, or oversee a business website, writing effective alt text should be a regular part of your content process. It ensures that your site is inclusive, informative, and optimized for performance across all devices and audiences.
Remember the key best practices:
✔ Be descriptive but concise
✔ Use relevant keywords naturally
✔ Skip decorative images using alt=””
✔ Localize content when appropriate
✔ Audit your site regularly to fill in any gaps
You don’t have to do it all manually, either. AI tools like ChatGPT can help you generate alt text quickly and consistently, especially when dealing with large volumes of images. With a clear prompt and a little editing, you can speed up your workflow without sacrificing quality.
Finally, make regular audits a habit. Use your CMS tools, SEO plugins, or site audit platforms to catch missing or weak alt text and ensure ongoing compliance and optimization.
By making alt text a routine part of your content strategy, you not only improve your site’s search visibility—you also make the internet a more accessible place for everyone.
Start small, stay consistent, and let your images speak volumes—even without being seen.
FAQ Section: Alt Text — Common Questions Answered
1. What is alt text in images?
Answer: Alt text (alternative text) is a short written description of an image that helps users understand its content when the image can’t be seen, such as for screen readers or when the image fails to load.
2. Why is alt text important for accessibility?
Answer: Alt text allows visually impaired users using screen readers to understand image content, making your website more inclusive and compliant with accessibility standards like WCAG.
3. How does alt text affect SEO?
Answer: Alt text helps search engines understand and index image content, improving your chances of ranking in image search results and enhancing overall page SEO.
4. What is the ideal length of alt text?
Answer: The ideal alt text length is under 125 characters. This keeps descriptions concise and readable by screen readers without overwhelming users.
5. Should every image have alt text?
Answer: No. Only informative or functional images should have alt text. Decorative images should use a null alt=”” attribute so screen readers can skip them.
6. Can I include keywords in my alt text?
Answer: Yes, include relevant keywords naturally. Don’t force them—focus on writing a helpful description that reflects the image content.
7. How do I add alt text to images on my website?
Answer: Use your CMS (like WordPress) to add alt text through the media library or image block settings. You can also add it manually in the HTML using the alt attribute.
8. What are examples of good alt text?
Answer: Good example:
“Golden retriever puppy playing with a red ball in a backyard.”
Bad example:
“Image of a dog.”
Good alt text is descriptive, specific, and relevant to the image context.
9. How often should I audit my website’s alt text?
Answer: Aim to review your alt text quarterly or after major content updates. Regular audits help maintain SEO performance and ensure accessibility compliance.
10. Can I use AI to write alt text?
Answer: Yes, AI tools like ChatGPT can generate alt text suggestions quickly. Just provide the image and desired keywords or character limits, then refine the result for clarity and accuracy.