Image Optimization Checker

Check for missing dimensions, lazy loading and modern formats.

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Images are usually the heaviest thing on a page, which makes them the biggest opportunity to speed it up. Serving a huge file scaled down in the browser, skipping modern formats, omitting dimensions and not lazy-loading off-screen images all waste bandwidth and time. An image optimization checker audits these issues so your pages load lighter and steadier.

What it checks

Oversized images served larger than they display
Missing width and height attributes that cause layout shift
Off-screen images that are not lazy-loaded
Opportunities to use modern formats (WebP, AVIF)
Uncompressed or needlessly large image payloads

Why it matters

Heavy images slow loads, eat mobile data, and — when they arrive without reserved dimensions — shove the page around as they appear, hurting both experience and Core Web Vitals. Optimising images is often the single biggest performance win, and it is mostly mechanical once you know which images to target.

How BrandSentryPro does it

Add your site and BrandSentryPro inspects your images for size, format, dimensions and loading strategy, lists what to fix, and re-checks as you publish new content.

Frequently asked questions

Why do images need width and height attributes?

Specifying dimensions lets the browser reserve space before the image loads, preventing the page from jumping around as images appear. That layout shift hurts user experience and Core Web Vitals.

What image format should I use?

Modern formats like WebP and AVIF typically deliver much smaller files than JPEG or PNG at similar quality. Serving them where supported significantly reduces page weight.

What is lazy loading?

Lazy loading defers loading off-screen images until the user scrolls near them, so the initial page load is lighter and faster. A checker flags images that should be lazy-loaded but are not.