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On-Page SEO

What Is Image Optimization?

Image optimization is the process of reducing image file sizes and improving delivery without sacrificing visual quality. It includes compression, format selection (WebP, AVIF), responsive sizing, lazy loading, and descriptive alt text. Optimized images load faster and consume less bandwidth.

Why Image Optimization matters for SEO

Images are typically the largest files on a web page and the #1 cause of slow LCP scores. Unoptimized images directly hurt Core Web Vitals, page speed, and user experience. Proper image optimization can reduce page weight by 40-80%.

Pro tip on Image Optimization

Convert images to WebP or AVIF format. Compress images (target 80% quality). Set explicit width and height attributes (prevents CLS). Implement lazy loading for below-fold images. Use responsive images with srcset. Add descriptive alt text.

Related terms

LCPHero images are usually the LCP element; optimizing them directly improves LCPPage SpeedImage optimization is the highest-ROI page speed improvementAlt TextAlt text is the SEO component of image optimizationCLSImages without dimensions cause layout shifts

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