Quick answer

Reduce transfer size, improve rendering speed, and protect visual quality with practical image optimization.

Bytes affect render time

Smaller images use less bandwidth and can complete sooner, especially on mobile networks. Correct dimensions also reduce decoding memory and prevent wasteful transfers.

Compression is one part of delivery

Use responsive sources, explicit dimensions, lazy loading below the fold, suitable caching, and a CDN alongside good compression settings.

Protect the largest visible image

The likely largest-contentful image should be discoverable early, appropriately sized, and not delayed by unnecessary scripts. Reserve its dimensions to avoid layout shift.

Next step: Use the related browser tool to apply these ideas and verify the result in its destination system.