Performance

Image size

Checks if images are optimized for the web.

Why does this matter?

Unoptimized images are often the largest contributor to heavy page weight. A 3 MB photo shown as a 300px thumbnail is pure waste of bandwidth and load time.

How to fix it?

Scale images to the maximum display size before uploading. Compress with tools like Squoosh, TinyPNG or ImageOptim. Use width and height attributes to prevent Layout Shift.

This check scores from 0 to 100. Below 50 is a fail, 50 to 89 is a warning, 90 or above is good. After each crawl you see the score per page in your report, with a short note on what we found.

Frequently asked questions

Checks if images are optimized for the web.

Unoptimized images are often the largest contributor to heavy page weight. A 3 MB photo shown as a 300px thumbnail is pure waste of bandwidth and load time.

Scale images to the maximum display size before uploading. Compress with tools like Squoosh, TinyPNG or ImageOptim. Use width and height attributes to prevent Layout Shift.

Example

Copy the code below and adapt the domain name, brand name and content to your situation.

<img
    src="/images/hero-800.webp"
    srcset="/images/hero-400.webp 400w,
            /images/hero-800.webp 800w,
            /images/hero-1600.webp 1600w"
    sizes="(max-width: 768px) 100vw, 50vw"
    alt="SEO dashboard for yourdomain.com"
    width="800"
    height="450"
    loading="lazy"
>
<!-- Scale image to maximum display size before uploading -->
<!-- Use WebP/AVIF for 25-50% smaller files than JPEG -->
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