Blog post image on how to optimize SEO images

Image SEO: How to Do SEO for Your Images

This blog post provides a comprehensive guide on how to do SEO for your images, ranging from basic SEO tips like using descriptive alt texts to technical SEO practices like adding structured data.

A few months ago, one of Astract’s clients—a restaurant owner—noticed a something surprising. Despite having a beautifully designed website, their online orders remained flat. After a quick audit, we discovered the issue: their product images, though stunning, were not optimized for search engines. Once we implemented some essential Image SEO techniques, the restaurant’s visibility and online sales improved significantly.

In this week’s blog post, we get into the best practices for Image SEO in 2025, equipping you with tools and techniques to improve rankings, loading speed, and overall website performance.

What is Image SEO?

Image SEO is the practice of optimizing images on your website so that search engines can easily find, understand, and index them. By enhancing elements such as file names, alt text, and compression, Image SEO ensures that your visuals contribute to your site’s rankings. It also improves page loading speeds, enhances accessibility, and increases engagement—all critical components of a high-performing website.

How Search Engines Index and Understand Images

Search engines rely on metadata, alt text, and contextual cues to interpret images. While advanced AI enables Google to analyze image content visually, it still depends heavily on associated text-based information. Here’s how search engines process images:

i. Crawling: Bots scan your site and detect image files.

ii. Indexing: Metadata (like file names and alt text) helps engines categorize the image.

iii. Ranking: The image’s relevance to a query and its optimization quality determine its position in search results.

    If your images aren’t optimized, search engines might skip them, leaving your content less competitive.

    How to Optimize Images for SEO: 15 Important Image SEO Tips

    As web pioneer Tim Berners-Lee famously said, “The power of the web is in its universality.” This universality includes not only text but also visual content, which forms a cornerstone of user experience today. With search engines like Google prioritizing visual search, optimizing images for SEO has become crucial for businesses aiming to scale. Let’s get into some Image SEO optimization tips you should know:

    1. Find or Create Valuable Images

    Using relevant and high-quality images can make or break your website’s appeal. A visual that complements your text not only engages users but also signals to search engines that your content is useful and relevant. When sourcing images:

    i. Use Stock Platforms:

    Websites like Unsplash, Pexels, and Shutterstock offer professional-grade stock photos. For businesses needing consistency in branding, Adobe Stock provides extensive customizable options.

    ii. Create Custom Images:

    Tools like Canva, Adobe Photoshop, and Figma allow for unique, tailored visuals. Custom images often perform better as they directly reflect your brand and avoid overuse.

    iii. Prioritize Relevance:

    Images should match the content they accompany. For instance, a website selling handmade pottery should display images of pottery-making processes and final products, not generic kitchenware photos.

    Always ensure the images you choose align with your message while keeping quality and relevance in focus.

    2. Choose the Right Image Format

    The format you use for images has a significant impact on performance, from loading speeds to visual clarity. Let’s explore the most common formats:

    i. SVG: Perfect for logos, icons, and vector-based graphics. SVGs are resolution-independent and remain sharp on all devices.

    ii. WebP: Google’s recommended format for its efficiency. WebP images are smaller in size while maintaining high quality, making them ideal for most website visuals.

    iii. JPG (or JPEG): Best for photos and complex imagery. JPGs strike a balance between file size and quality, making them a go-to choice for online portfolios and product images.

    iv. PNG: Use PNG for images requiring transparency or high-detail graphics. However, PNG files can be large, so use sparingly.

    v. GIF: Commonly used for animations or simple motion graphics. GIFs add personality but can slow a page if overused.

    Choose the right format based on the image’s purpose to ensure both performance and aesthetics. For icons, opt for SVG; for product photos, stick with JPG or WebP.

    3. Give Your Images Descriptive File Names

    Descriptive file names help search engines understand what an image represents. Many people make the mistake of uploading images with default file names like IMG1234.jpg or Screenshot1.png. These names provide no context, making it harder for Google to categorize the image.

    Descriptive file names improve your chances of appearing in image search results, as Google uses every piece of information to assess content relevance.

    chocolate cup cake with white and red sprinkles
    Best Practices:

    a. Avoid keyword stuffing; keep the name natural and concise.

    b. Use specific, relevant keywords in your file names.

    c. Separate words with hyphens (e.g., chocolate-cupcakes-recipe.jpg). Avoid spaces or underscores

    For example, if you’re uploading an image of a handmade vase, use a file name like handmade-ceramic-vase.jpg instead of IMG1234.jpg.

    4. Write SEO-Friendly Alt Text

    Alt text (alternative text) is critical for accessibility and SEO. It describes the content of an image for screen readers, helping visually impaired users understand what’s on the page. Additionally, search engines rely on alt text to index images properly.

    How to Write Effective Alt Text:

    1. Be Descriptive: Accurately describe what’s in the image. For instance, for a picture of a latte, use Alt=”A steaming latte with heart-shaped foam in a ceramic cup on a wooden table.”

    2. Include Keywords Naturally: Incorporate primary or secondary keywords without overdoing it. Example: Alt=”Handcrafted ceramic vase in a rustic design, ideal for home decor.”

    3. Avoid Keyword Stuffing: Overloading alt text with keywords (e.g., Alt=”Best vase, ceramic vase, buy vases online”) can harm your SEO.

      Alt Text Examples:

      Good: Alt=”Blue ceramic vase on a wooden table with a sunflower arrangement.”

      Bad: Alt=”Blue vase, blue vase photo, buy blue vase.”

      Alt text isn’t just about SEO—it enhances user experience and accessibility, which are equally important.

      5. Resize Images for Faster Loading

      Uploading oversized images is one of the most common mistakes in web design. Large files slow your website, leading to higher bounce rates and lower search rankings. Resizing images ensures they are optimized for speed without compromising quality.

      Best Practices for Resizing Images:

      i. Understand Context: 

      The size you choose depends on the image’s role. For instance:

      • Hero images or banners: 1920px wide for full-screen layouts.
      • Blog post images: 1200px wide or smaller.
      • Thumbnails: 150–300px wide.

      ii. Match Device Expectations: 

      Consider the devices your audience uses. Desktop images can be larger, but for mobile, aim for compact sizes.

      iii. Maintain Aspect Ratios: 

      Avoid distortion by keeping consistent proportions when resizing.

      You can use tools like TinyPNG, and Adobe Photoshop for control over image sizes and dimensions. You can also use Online Resizer Tools like Pixlr or Fotor for quick resizing options. With resized images, your site will load faster, reducing frustration for users and improving rankings.

      6. Compress Images Without Losing Quality

      Image compression reduces file size while maintaining visual integrity. Compression is vital for ensuring faster load times and reducing bandwidth usage, especially for mobile visitors. 

      Search engines prioritize fast-loading websites and Compressed images are best to save server storage and improve user experience. Poorly compressed images apart from their large sizes can appear pixelated, harming your brand’s credibility.

      Best Practices: How to Compress Images:
      • Use lossless compression for high-quality visuals (retains all data).
      • Use lossy compression when slight quality reduction is acceptable for performance gains.
      • Always preview images after compression to ensure they still look appealing on all devices.

      Some great tools you can use for compression include TinyPNG, ImageOptim (best for batch compression on macOS), and Squoosh by Google.

      7. Use Responsive Image Scaling

      Responsive image scaling ensures that images adapt seamlessly to various screen sizes, from desktops to smartphones. With mobile devices accounting for a large portion of web traffic, this practice is no longer optional.

      Optimized images have faster loading time and Google prioritizes these websites in search results. Mobile-friendly images also  fit neatly on any screen, eliminating awkward cropping.

      How to Implement Responsive Scaling:
      • Use the <picture> HTML element to serve different image sizes for different devices.
      • Add CSS rules like max-width: 100%; height: auto; to make images scale proportionally.
      • For WordPress users, plugins like WP Retina 2x or Smush handle responsive images automatically.

      Responsive image scaling improves aesthetics, performance, and accessibility—all of which contribute to higher search.

      a graphical representation of an image sitemap for image seo

      8. Create an Image Sitemap

      An image sitemap is a file that lists all the images on your website, providing metadata to help search engines index them effectively. While search engines crawl images naturally, a dedicated sitemap ensures no visual content gets overlooked, especially if your images are loaded dynamically (e.g., via JavaScript).

      Image Sitemap helps search engines discover images they might miss otherwise. This increases the likelihood of images appearing in Google Images search results, contributing to the overall content relevance of your site.

      How to Create an Image Sitemap:

      a. Use Tools or Plugins: If you’re on WordPress, plugins like Yoast SEO or Rank Math automatically generate sitemaps that include images.

      b. Manually Add Images to Your Sitemap: Include tags within your XML sitemap. Each tag should specify:

      • URL of the image (<image:loc>)
      • Title or caption (<image:title>)

      c. Submit Your Sitemap: Once your sitemap is ready, submit it to Google Search Console for indexing.

        For example, a sitemap entry for an image might look like this:

        xml

        <url>

          <loc>https://www.yourwebsite.com/gallery/summer-beach.jpg</loc>

          <image:image>

            <image:loc>https://www.yourwebsite.com/gallery/summer-beach.jpg</image:loc>

            <image:title>Summer Beach at Sunset</image:title>

          </image:image>

        </url>

        Using a sitemap is one of the best practices for Image SEO in 2024, ensuring comprehensive visibility.

        9. Enable Browser Caching

        Browser caching stores website data (like images) locally on a visitor’s device, allowing pages to load faster on return visits. For image-heavy websites, caching can significantly reduce load times and improve the user experience. Cached images load directly from the user’s device instead of downloading from the server, boosting the loading time. Fewer requests to your server mean better site performance during high traffic and better SEO performance. 


        image cache illustration
        How to Enable Browser Caching:

        i. Modify Your .htaccess File: For Apache servers, add the following code to set an expiration time for images:

        <IfModule mod_expires.c>

            ExpiresActive On

            ExpiresByType image/jpg “access plus 1 year”

            ExpiresByType image/jpeg “access plus 1 year”

            ExpiresByType image/png “access plus 1 year”

            ExpiresByType image/gif “access plus 1 year”

          </IfModule>

          ii. Use a Caching Plugin: If you use WordPress, plugins like W3 Total Cache or WP Rocket make enabling caching effortless.

          iii. CDN Integration: Content Delivery Networks (CDNs) like Cloudflare or Amazon CloudFront automatically handle caching and improve global delivery speeds.

          Caching optimizes both user experience and SEO, making it a must-have for image-heavy websites.

          10. Add Structured Data

          Structured data, or schema markup, enhances how search engines interpret and display your content. For images, structured data is particularly useful in enabling features like Google Rich Results or Image Carousels. Structured data showcases product images, recipes, or creative works directly in search results. This helps Google categorize your images more accurately and encourage more clicks through engaging previews.

          How to Implement Structured Data for Images:

          a. Use JSON-LD Markup: Add structured data for products, recipes, or events. For example, an image in a product schema might look like this:
          Json

          {

              “@context”: “https://schema.org”,

              “@type”: “Product”,

              “name”: “Ceramic Vase”,

              “image”: “https://www.yourwebsite.com/images/ceramic-vase.jpg”,

              “description”: “A handmade ceramic vase with a rustic finish.”

            }

            b. Validate with Testing Tools: Google’s Structured Data Testing Tool or Rich Results Test can verify your schema implementation.

              By combining schema markup with Image SEO techniques for faster website loading, you increase your chances of dominating search results.

              11. Serve Images via an Image CDN

              A Content Delivery Network (CDN) accelerates website performance by delivering content from servers closest to the user’s location. Specialized image CDNs go a step further by optimizing images on the fly. CDN encourages faster delivery for users in different locations. CDNs like Cloudinary or Imgix, resize and compress images dynamically leading to reduced road times lead and better rankings.

              How to Set Up an Image CDN:

              i. Choose a Provider: Platforms like Cloudinary, Imgix, or KeyCDN are tailored for images.

              ii. Integrate with Your Website: Most CDNs provide plugins or APIs for easy integration.

              iii. Optimize Settings: Enable features like lazy loading, responsive scaling, and WebP conversions.

                With a CDN, you not only improve image search rankings but also deliver a seamless experience to global audiences.

                12. Pay Attention to Copyright

                Using copyrighted images without permission can lead to legal issues and financial penalties. Additionally, Google penalizes sites that duplicate content, including images, from other sources.

                How to Avoid Copyright Issues:

                Use Royalty-Free Sources: Stick to platforms like Pexels, Unsplash, or Pixabay, where images are licensed for commercial use.

                Attribute Properly: Some licenses (like Creative Commons) require you to credit the creator.

                Create Your Own Content: Invest in custom visuals to avoid copyright concerns entirely.

                Remember, respecting copyright not only keeps your site ethical but also ensures credibility in your branding efforts.

                13. Apply On-Page SEO Best Practices

                On-page SEO involves optimizing all elements of your webpage, including images, for maximum search engine visibility.

                Essential On-Page Image SEO Elements:

                Title Tags: Include relevant keywords in the title tag of the page containing the image.

                Meta Descriptions: Add engaging and keyword-rich descriptions to encourage clicks.

                Captions: While not mandatory, captions can improve user engagement and clarify context for readers.

                  Example:

                  image seo example: 3 ceramic faces, the middlee one has some flowers in it

                  For a blog post titled “Top Handmade Vase Designs in 2024,” ensure:

                  • The image file name is handmade-vase-2024.jpg.
                  • The alt text is Alt=”A rustic handmade ceramic vase from 2024 collection.”
                  • The meta description mentions keywords like “handmade vase” and “unique ceramic designs.”

                  Applying on-page SEO best practices ensures your images work in tandem with the rest of your content to improve visibility and engagement.

                  Conclusion

                  Image SEO is more than just uploading beautiful pictures. It’s also abut following some image optimization best practices—like choosing the right formats, writing descriptive alt text, compressing files, and implementing structured data. 

                  At Astract, we understand the importance of a visually stunning yet performance-driven website. By leveraging these SEO tips for images in WordPress and beyond, you can make your content accessible, engaging, and search engine-friendly. 

                  FAQs: Image SEO

                  Why is alt text important for image SEO?

                  Alt text improves accessibility and helps search engines understand the image content, boosting rankings.

                  What’s the best format for images?

                  WebP is ideal for most cases due to its small size and high quality. PNG is great for transparent images, while SVG works best for icons.

                  How do I compress images without losing quality?

                  Tools like TinyPNG, Squoosh, or ImageOptim reduce file sizes while maintaining visual integrity.

                  Can stock images rank in image search?

                  Yes, but custom visuals generally perform better as they provide unique value and branding.

                  By integrating these image SEO techniques for faster website loading, you’re setting the stage for a website that looks great and performs even better.

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