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🖼️Performance100% Free Utility
Image Size Analyzer
Identifies uncompressed images, missing intrinsic dimensions, and assets scaled down via CSS that degrade mobile performance.
Run Image Size Analyzer
Reference Benchmark: Content imagery in WebP/AVIF under 150KB
What This Metric Means for Your Site
Unoptimized images represent the largest single component of website weight on the modern web and are a primary driver of mobile LCP issues.
How to Improve Your Score (Actionable Fixes)
- Always serve images in modern next-gen formats like WebP or AVIF.
- Provide responsive srcset attributes to serve scaled dimensions to mobile viewports.
- Specify explicit width and height attributes on every img tag to lock layout geometry.
Recommended Guide
Read GuideZero CLS Web Design: How to Eliminate Visual Shifts Forever
Cumulative Layout Shift frustrates users and lowers Core Web Vitals rankings. Learn how aspect ratio containers, font fallback overrides, and fluid clamp typography prevent sudden visual jumps on mobile devices.
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Page Weight Checker
Break down total transfer bytes across JavaScript, CSS, images, and fonts.
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Isolate exact DOM elements, generate white-label PDF audit summaries, and export outreach lead lists in 50ms from any live Chromium tab.