Image Optimisation Guide
Learn how to optimize images for faster loading, better SEO, and improved accessibility while maintaining visual quality.
Benefits of Image Optimisation
Properly optimised images are crucial for both user experience and SEO performance.
Faster Page Load Times
Optimized images reduce file sizes and improve loading speed
Better SEO Performance
Properly optimized images can appear in image search results
Improved Accessibility
Alt text helps visually impaired users understand image content
Enhanced User Experience
Fast-loading, relevant images improve engagement and satisfaction
Image Optimisation Techniques
Use these proven approaches to optimise your images for web use.
File Format Selection
Choose the right format for each type of image
- Use WebP for modern browsers (best compression and quality)
- Use JPEG for photographs and complex images
- Use PNG for graphics with transparency or simple colors
- Use SVG for logos, icons, and vector graphics
- Consider AVIF for next-generation compression (where supported)
Compression and Resizing
Reduce file sizes without sacrificing visual quality
- Resize images to match their display dimensions exactly
- Compress images to balance quality and file size
- Use lossless compression for graphics and simple images
- Use lossy compression for photographs where minor quality loss is acceptable
- Test different compression levels to find the optimal balance
Alt Text Optimisation
Write descriptive alt text for accessibility and SEO
- Be descriptive but concise (125 characters or less)
- Include relevant keywords naturally when appropriate
- Focus on the image's purpose and context
- Don't start with 'image of' or 'picture of'
- Decorative images should have empty alt attributes (alt='')
Responsive Implementation
Ensure images work well on all devices and screen sizes
- Use srcset attribute for multiple image sizes
- Implement proper width and height attributes
- Use CSS to make images responsive (max-width: 100%)
- Consider lazy loading for below-the-fold images
- Test images on various devices and screen resolutions
How to Optimise Your Images
Follow this systematic approach to effectively optimise your images.
Audit Existing Images
Analyze your current image optimisation status
- Use tools like Google PageSpeed Insights or GTmetrix
- Identify images that are too large or uncompressed
- Check for missing or poor alt text
- Find images without proper dimensions specified
- Note images that aren't responsive on mobile devices
Optimise Image Assets
Process and compress images for web use
- Choose appropriate file formats for each image type
- Resize images to match their display dimensions
- Compress images using tools like TinyPNG or ImageOptim
- Save images for web with appropriate quality settings
- Create multiple sizes for responsive implementation
Implement Proper Markup
Add optimized images to your web pages
- Include descriptive alt text for all non-decorative images
- Specify width and height attributes to prevent layout shifts
- Use srcset for responsive images with multiple sizes
- Implement lazy loading for better performance
- Add appropriate image titles when beneficial
Add Structured Data
Enhance images with schema markup for rich results
- Implement ImageObject schema for key images
- Include copyright and creator information when relevant
- Add license information for stock or licensed images
- Use appropriate image properties in structured data
- Validate schema markup with Google's Rich Results Test
Monitor and Maintain
Regularly review and update image optimisation
- Monitor page speed and Core Web Vitals scores
- Check image indexing in Google Search Console
- Audit alt text for accuracy and relevance
- Update images when content changes
- Stay current with new image formats and optimisation techniques
Best Practices
Follow these guidelines to maximize your image optimisation effectiveness.
Do: Prioritize User Experience
Optimise images to enhance, not detract from, user experience
Do: Use Modern Formats
Take advantage of WebP and AVIF for better compression
Do: Implement Lazy Loading
Load images only when they're about to enter the viewport
Do: Test Across Devices
Ensure images look good and load quickly on all devices
Common Mistakes to Avoid
Steer clear of these pitfalls that can harm your image optimisation efforts.
Don't: Use Large Original Files
Uploading camera photos directly without optimisation
Don't: Forget Alt Text
Missing alt text hurts accessibility and SEO
Don't: Skip Responsive Images
Images that don't adapt to different screen sizes
Don't: Ignore File Naming
Using generic filenames like IMG_1234.jpg instead of descriptive names
Ready to Optimise Your Images?
Proper image optimisation can significantly improve your site's performance and search rankings. Our team can audit your images and implement optimisations that enhance both user experience and SEO.
Pro Tip: Implement a systematic image optimisation workflow for your content team. Create a checklist that includes file format selection, compression, alt text, and responsive implementation for every image.