How to Write Image ALT Text for Products, Logos & Charts?

Imagine showing your friend a picture of a dog. Even if you say nothing, your friend can understand the image—they can notice the dog’s color, size, and even whether it looks happy or sad.

But what if the person cannot see? They wouldn’t know what’s in the image. Similarly, search engines like Google and Bing cannot “see” images the way humans do. They rely on descriptive signals to understand the content of images.

This is where ALT text comes in. It tells search engines and visually impaired users what the image shows, improving both image SEO and web accessibility. Properly optimized picture ALT text for SEO helps your images rank for relevant queries, appear in Google Images, and support voice search.

What is image alt text for SEO?

ALT Text (Alternative Text) is a short, descriptive sentence added to an image on your website. It provides a textual explanation of the image so that search engines, screen readers, and users who cannot see the image can understand its content. ALT text is a crucial part of image SEO, helping your images rank in Google Images, improving web accessibility, and giving your webpage additional SEO value.

Optimizing ALT text helps search engines understand the context of images, associate them with relevant keywords, and improve the overall relevance of your web pages. For users, ALT text ensures that screen readers can convey meaningful information about images, which is especially important for visually impaired visitors.

Why Is It Called “Alternative” Text?

ALT text is called “alternative” because it acts as a backup for images. If an image fails to load due to slow internet, a technical error, or if images are disabled manually, the ALT text appears in its place. This allows both users and search engines to understand what the image represents even when it cannot be displayed.

Why ALT Text Matters

ALT text is important for several key reasons:

• Search engines: It allows Google, Bing, and other search engines to understand your images and index them for relevant search queries. Properly optimized ALT text can improve your image search visibility and drive organic traffic.
• Accessibility: ALT text ensures that visually impaired users, relying on screen readers, can understand the content of images.
• Page SEO: Images with descriptive ALT text contribute to your overall on-page SEO, improving relevance and user experience.
• User experience: ALT text provides context when images fail to load or for users with slow internet connections.

When Image ALT Text is Most Useful

ALT text becomes especially valuable in situations such as:

• When an image cannot be displayed due to technical issues.
• When users disable images or have slow internet connections.
• When screen readers are used by visually impaired users.
• When optimizing your site for image search and SEO visibility.
  

How Search Engines Read Image ALT Tag? 

Search engines read image ALT tags as descriptive text that explains an image’s content and purpose. ALT tags help improve accessibility, provide context when images fail to load, and support SEO by helping images rank in search results.

• Entities: lion, tree, grassland
• Action: resting
• Location or environment: nature, wildlife
• Object type: animal, African wildlife

How to Write ALT Text for SEO and Accessibility

Image ALT text is a short text description added to an image to improve SEO and web accessibility.
To write effective ALT text, describe the image clearly and concisely, avoid keyword stuffing, and focus only on important visual details. Use empty ALT text (alt="") for decorative images so screen readers can skip them.

1. Describe the Image Clearly

Describing the image clearly is a core best practice for writing effective ALT text for SEO and accessibility.
ALT text should accurately represent what is visible in the image without adding unnecessary words or imaginary details.

ALT text should describe:

• Only what the image actually contains.
• Real people, objects, and environments.
• Important visual details that support understanding.

Example Image:
A young girl is eating vanilla ice cream outdoors.

Good ALT Text:
“A young girl eating vanilla ice cream in a park.”

Bad ALT Text:
“Kids enjoying ice cream, summer party, fun food.”
(These details are not present in the image.)

Effective ALT text is:

• Direct — states exactly what appears in the image.
• Honest — avoids assumptions or fictional details.
• Simple — easy for screen readers to interpret.
• Descriptive — includes real entities such as girl, ice cream, park, food, and outdoors.

Using accurate entities helps search engines and assistive technologies understand the image content correctly.

2. Keep ALT Text Short and Simple

ALT text should be short, clear, and easy to read.
Long descriptions can confuse users and make screen readers difficult to follow.

Best practices:

Good Example:

“A brown cat sleeping on a white sofa.”

Bad Example:

“A medium-sized brown domestic cat with green eyes is comfortably sleeping on a large white sofa in a modern living room.”

Reason: Long ALT text is too detailed and tiring for users and screen readers. Short, descriptive text improves accessibility and SEO.

3. Do Not Keyword Stuff in ALT Text

ALT text should describe the image naturally and truthfully. Adding too many keywords in ALT text does not improve rankings and can hurt both SEO and user experience.

Best practices:

Example:

“Red running shoes for women placed on a white background.”

“Best red running shoes for women, red shoes women’s running shoes buy red shoes”

Reason: Keyword-stuffed ALT text is ignored or penalized by search engines and decreases accessibility for screen readers.

4. Include Context in ALT Text

ALT text should reflect the context and purpose of the page, not just describe the object.
The same image may require different ALT text depending on the page topic.

Example Image: Smartphone

“Black Samsung Galaxy S23 Ultra smartphone front view.”

“A smartphone used for online learning.”

Rule: When the same image appears on different pages, write ALT text that supports the page topic. This improves SEO, accessibility, and user experience.

5. Avoid Starting ALT Text with “Image of” or “Picture of”

Search engines and AI models treat phrases like “Image of” or “Picture of” as redundant.
ALT text should start with the subject, followed by relevant details, context, or style.

Example: Boy riding a bicycle

“Image of a boy riding a bicycle.”

“A boy riding a bicycle.”

Reason: Starting directly with the subject makes ALT text concise, descriptive, and more effective for SEO and accessibility.

6. ALT Text Should Only Describe Important Elements

ALT text should focus on the essential elements of an image, not every detail.
Describing irrelevant or minor elements makes ALT text long, confusing, and less useful for SEO and accessibility.

Focus on these key elements:

Avoid describing:

Example: Image of a teacher teaching students in a classroom

“A female teacher explaining a lesson to students in a classroom.”

“A teacher in a green shirt standing near a whiteboard with five students sitting on brown chairs facing her.”

Reason: Focused ALT text is concise, descriptive, and helps search engines and screen readers understand the image clearly.

7. Use Empty ALT Text (alt="") for Decorative Images

Not all images require ALT text.
Decorative images, which do not convey meaningful content, should have empty ALT text to improve accessibility.

Examples of decorative images:

Reason: Adding ALT text to decorative images can confuse visually impaired users. Using alt="" ensures screen readers ignore these images and only read meaningful content. This improves accessibility and user experience.

8. Write ALT Text in a Natural, Human-Friendly Way

ALT text should be easy to read, natural, and descriptive.
Avoid robotic or keyword-stuffed phrases that do not make sense.

Example:

“Man holding laptop computer standing outside company building corporate business concept.”

“A man holding a laptop while standing outside an office building.”

Reason: Human-friendly ALT text improves readability, accessibility, and search engine understanding of the image.

Complete Guide to Writing SEO-Friendly ALT Text for Images

Writing effective ALT text is essential for image SEO, improving Google Images ranking, enhancing voice search accuracy, and ensuring web accessibility. ALT text should describe the content of an image clearly, convey its purpose, and include relevant keywords naturally.

1. ALT Text for Product Images (E-commerce SEO)

Describe the product name, color, type, angle, and unique features. Include the usage context if relevant. This helps Google Shopping, image search visibility, and user experience.

Example:

Best practices:

Further Reading: E-commerce SEO

2. ALT Text for Photos of People

Describe the role, action, emotion, and optionally the location. Avoid assumptions about race, age, or appearance unless specified.

Example:

Best practices:

3. ALT Text for Logos (Brand & Clickable Links)

Clearly identify the brand name. If the logo is clickable, specify the destination page.

Examples:

Best practices:

4. ALT Text for Infographics

Summarize the main concept instead of every detail. Highlight what the user should learn.

Examples:

Best practices:

5. ALT Text for Charts & Graphs

Describe the insight or trend, not the visual style or colors. Convey the meaning.

Examples:

Best practices:

6. ALT Text for Screenshots

Describe the app, dashboard, website, or tutorial screen, including important elements visible.

Examples:

Best practices:

7. ALT Text for E-Commerce Galleries

Each image must have unique ALT text for better ranking. Include angle, variation, color, style, or usage context.

Examples:

Best practices:

8. ALT Text for Complex Images (Maps, Technical Drawings, Diagrams, UI Flows)

Provide a concise summary in ALT text, then a detailed description in surrounding text if necessary.

Examples:

Best practices:

Key Takeaways: ALT Text for SEO and Accessibility

FAQs: ALT Text, Tools, and Accessibility

1. Which AI tools can automatically generate ALT text for images?

Popular AI tools for generating descriptive ALT text include ChatGPT, AutoAlt.ai, AltTextLab, GoPublish, iWeaver, PixSays, AIHumanSpace, Popupsmart, Pallyy, and MyMap.AI. These tools automatically create meaningful ALT text to improve image SEO and accessibility for visually impaired users.

2. What tools help developers find missing or problematic ALT text?

Developers can use Lighthouse, WAVE, or Screaming Frog SEO Spider to identify missing or inaccurate ALT text on websites. These tools analyze HTML, report issues, and suggest corrections to enhance image SEO and accessibility compliance.

3. What are the WCAG guidelines for ALT text?

According to WCAG (Web Content Accessibility Guidelines), all important images should have short, clear, and accurate ALT text. This ensures that visually impaired users understand the content of images, supporting screen readers and improving overall web accessibility.

4. What are ARIA roles, and when should they be used?

ARIA (Accessible Rich Internet Applications) roles help screen readers interpret interactive elements:

Using ARIA roles enhances accessibility beyond ALT text, especially for complex user interfaces and interactive elements.