Website Image Analyzer
See how much your images weigh and how to make them lighter. The analyzer measures the size and format of up to 60 images on a page and checks what matters for speed: modern formats such as WebP and AVIF, files over 200 KB, width and height attributes that prevent layout shifts, lazy loading for images further down, a first image that is not lazy-loaded, and srcset for smaller screens. A score sums it up.
- Encrypted connection
- No sign-up
- Free to use
How to use Website Image Analyzer
- Enter the page address.
- Click “Analyse images”.
- Read the score and checks.
- Optimise the images flagged.
Website Image Analyzer features
Total weight
All image bytes.
Formats
JPEG, PNG, WebP, AVIF, SVG.
Layout shift risks
Missing dimensions.
Lazy loading
First and later images.
Per-image findings
What to fix.
Safe fetching
Public addresses only, with size and time limits.
When to use Website Image Analyzer
- Speeding up heavy pages.
- Core Web Vitals work.
- Reviewing a new theme.
- Ecommerce product pages.
Website Image Analyzer FAQ
Why not lazy-load the first image?
The main image is often the Largest Contentful Paint; lazy loading delays it.
Why do width and height matter?
They let the browser reserve space, so the layout does not jump when the image arrives.
Which format should I use?
WebP for photos and graphics in most cases, AVIF for the smallest files, SVG for logos and icons.
Where are the sizes from?
From the servers’ responses for each image.
Should every image be lazy-loaded?
No. Images visible when the page first appears should load immediately. Lazy loading is for images further down the page.
What image size is too large?
There is no fixed rule, but images over about 200 KB usually deserve a look. Hero images can be larger; thumbnails and icons should be far smaller.
Which format should I use for photos?
WebP or AVIF for the web, with JPEG as a fallback if you support very old browsers. PNG is best for graphics with sharp edges or transparency, not for photos.
Lighter images, faster pages
Images are usually the largest part of a page. Converting to modern formats and serving the right size for each screen often halves the page weight.
The optimisers on this site convert and compress images in your browser.
Images are often the heaviest part of a page. The analyzer measures the real size and format of up to 60 images and checks the habits that keep pages fast: modern formats such as WebP and AVIF, no single image over about 200 KB, width and height attributes, and lazy loading for images below the fold.
Width and height attributes let the browser reserve space before the image loads, which prevents layout shifts (part of Core Web Vitals). The first large image, often the main content, should not be lazy-loaded – it should load as early as possible, ideally with fetchpriority="high".
Fix the largest files first: converting a 900 KB JPEG hero image to a well-compressed WebP or AVIF and serving smaller versions to phones with srcset usually saves more than many small tweaks.
A practical order for fixes: convert the largest images to WebP or AVIF, add width and height attributes to every image to prevent layout shifts, add loading="lazy" to images below the fold, and serve smaller versions to phones with srcset and sizes. Re-run the analyzer after each step to see how much weight you saved.