seo-images

Image Optimization Analysis Checks Alt Text Present on all elements (except decorative: role="presentation") Descriptive: describes the image content, not "image.jpg" or "photo" Includes relevant keywords where natural, not keyword-stuffed Length: 10-125 characters Good examples: "Professional plumber repairing kitchen sink faucet" "Red 2024 Toyota Camry sedan front view" "Team meeting in modern office conference room" Bad examples: "image.jpg" (filename, not description) "plumber plumbing plumber services" (keyword stuffing) "Click here" (not descriptive) File Size Tiered thresholds by image category: Image Category Target Warning Critical Thumbnails < 50KB > 100KB > 200KB Content images < 100KB > 200KB > 500KB Hero/banner images < 200KB > 300KB > 700KB Recommend compression to target thresholds where possible without quality loss. Format Format Browser Support Use Case WebP 97%+ Default recommendation AVIF 92%+ Best compression, newer JPEG 100% Fallback for photos PNG 100% Graphics with transparency SVG 100% Icons, logos, illustrations Recommend WebP/AVIF over JPEG/PNG. Check for element with format fallbacks. Recommended Element Pattern Use progressive enhancement with the most efficient format first: The browser will use the first supported format. Current browser support: AVIF 93.8%, WebP 95.3%. JPEG XL — Emerging Format In November 2025, Google's Chromium team reversed its 2022 decision and announced it will restore JPEG XL support in Chrome using a Rust-based decoder. The implementation is feature-complete but not yet in Chrome stable. JPEG XL offers lossless JPEG recompression (~20% savings with zero quality loss) and competitive lossy compression. Not yet practical for web deployment, but worth monitoring for future adoption. Responsive Images srcset attribute for multiple sizes sizes attribute matching layout breakpoints Appropriate resolution for device pixel ratios Lazy Loading loading="lazy" on below-fold images Do NOT lazy-load above-fold/hero images (hurts LCP) Check for native vs JavaScript-based lazy loading fetchpriority="high" for LCP Images Add fetchpriority="high" to your hero/LCP image to prioritize its download in the browser's network queue: Critical: Do NOT lazy-load above-the-fold/LCP images. Using loading="lazy" on LCP images directly harms LCP scores. Reserve loading="lazy" for below-the-fold images only. decoding="async" for Non-LCP Images Add decoding="async" to non-LCP images to prevent image decoding from blocking the main thread: CLS Prevention width and height attributes set on all elements aspect-ratio CSS as alternative Flag images without dimensions File Names Descriptive: blue-running-shoes.webp not IMG_1234.jpg Hyphenated, lowercase, no special characters Include relevant keywords CDN Usage Check if images served from CDN (different domain, CDN headers) Recommend CDN for image-heavy sites Check for edge caching headers Output Image Audit Summary Metric Status Count Total Images - XX Missing Alt Text ❌ XX Oversized (>200KB) ⚠️ XX Wrong Format ⚠️ XX No Dimensions ⚠️ XX Not Lazy Loaded ⚠️ XX Prioritized Optimization List Sorted by file size impact (largest savings first): Image Current Size Format Issues Est. Savings ... ... ... ... ... Recommendations Convert X images to WebP format (est. XX KB savings) Add alt text to X images Add dimensions to X images Enable lazy loading on X below-fold images Compress X oversized images Weekly Installs196Repositoryagricidaniel/claude-seoGitHub Stars2.5KFirst SeenFeb 19, 2026Security AuditsGen Agent Trust HubPassSocketPassSnykPassInstalled oncodex184github-copilot183opencode183gemini-cli182cursor182kimi-cli181