Website Image Optimization Checklist

Large images are the #1 cause of slow page loads and poor Core Web Vitals scores.

At 80% quality, file size drops 50–60% with no visible quality loss at normal viewing distances.

The Largest Contentful Paint (LCP) image directly affects your Google PageSpeed score.

Verify dimensions, file size, and get optimization recommendations before going live.

WEBP achieves 25–35% smaller files than JPEG at equivalent quality. Google recommends it for web performance.

PNG is lossless and supports transparency, but produces much larger files than JPEG for photos.

PNG photos are 3–5x larger than equivalent JPEG files. Converting saves significant bandwidth.

WEBP has 95%+ browser support, but a JPEG fallback ensures compatibility with older browsers.

A 4000×3000px image displayed at 800×600px wastes 25x the pixels. Always resize to display size.

Retina displays need 2x resolution, but going beyond 1600px wide is rarely necessary for web.

Avoid browser-side cropping which wastes bandwidth loading pixels that are hidden.

Each platform (Shopify, WordPress, Instagram) has specific dimension requirements for best display.

Alt text helps Google understand image content and improves accessibility for screen readers.

File names like 'product-red-sneakers-size-10.jpg' help Google index images for relevant searches.

EXIF data adds unnecessary file size and may expose GPS location or device information.

Schema.org markup for images can enable rich results in Google Search, increasing click-through rates.

Prevents layout shift (CLS) — a Core Web Vitals metric that affects Google rankings.

Lazy loading defers loading of off-screen images, improving initial page load time.

Adding <link rel='preload'> for the hero image can significantly improve LCP scores.

CDNs serve images from servers closest to the user, reducing latency globally.

Watermarks protect your copyright and brand your images when shared on social media.

Photos taken on smartphones contain GPS coordinates in EXIF data — a privacy risk.

Favicons appear in browser tabs, bookmarks, and search results — essential for brand recognition.