Are the images on my page slowing it down?
Images are usually the heaviest thing on a page. We look at three things you can see in the code: whether each image tells the browser its size, whether it uses a modern format, and whether images further down wait their turn to load. Together they decide how fast and how steadily a page appears.
What it actually is
Picture setting a table before the guests arrive. An image that declares its width and height is a place card: the browser saves the space and nothing moves when it lands. A modern format such as WebP or AVIF is the same picture packed into a smaller box. Lazy loading tells the browser not to fetch pictures far down the page until a reader gets near them.
Why it matters
An image with no size is one of the most common reasons a page jumps while it loads, the moment when a person reaches for a button and it slides away. Oversized files in old formats make the page slower to finish on a phone connection, and slow pages lose readers before they read anything.
What good looks like
Every image declares its dimensions, or has its space reserved some other way. Photos are served in a modern format at the size they are shown. Images below the first screen load only as a reader scrolls towards them, while the main picture at the top loads straight away.
Being honest about it
This does not move your score, and it never fails a page. Speed and layout shift belong to the Performance course, which measures them directly and is kept out of the headline on purpose, so this check is a pointer rather than a judgement. It reads the markup, not the file sizes, and a page with no images is left off the report.
Where most sites go wrong
The common pattern is a site that looked fine when it launched and then filled up with images uploaded straight from a camera or a design tool. The other is a template that writes images out with no size at all, or that lazy-loads the large picture at the very top, so the most important image is the last to arrive.
Not sure where yours stands?
A free scan checks this and everything else in about 20 seconds — no signup. Or if it's already flagged and you'd rather it were simply handled, we do that too.
Flagged for this one? We handle it. No pitch, just a plain-English chat.
Book a call