Pass Core Web Vitals by fixing the images first
Two of the three Core Web Vitals are heavily image-driven: the Largest Contentful Paint element is usually an image, and missing image dimensions cause layout shift. Optimagio finds the exact assets responsible and gives you the fixes — modern format, right size, and set dimensions.
- Identify the likely LCP image on any page
- Flag missing width/height that cause layout shift
- Ship WebP/AVIF at display size to lower LCP
Real product capability — not a placeholder.
How images drive Core Web Vitals
Core Web Vitals are Google’s page-experience metrics. Largest Contentful Paint (LCP) measures how quickly the largest visible element renders — on most pages that element is an image. Cumulative Layout Shift (CLS) measures unexpected movement, and a frequent cause is images without declared width and height that push content as they load.
What actually moves the metric
To improve LCP, the highest-impact steps are: serve the LCP image in a modern format (WebP/AVIF), resize it to its real display dimensions, and avoid render-blocking delays. To improve CLS, give images explicit dimensions so the browser reserves their space. Optimagio’s audit detects each of these issues per page and the optimizer fixes the ones it can.
Fix Core Web Vitals image issues
- 1
Audit the page
Run a free image audit to find the likely LCP image, oversized assets, and missing dimensions.
- 2
Modernize the LCP image
Convert it to WebP or AVIF and resize it to the dimensions it actually renders at.
- 3
Set width and height
Add explicit dimensions to images flagged as missing them to stop layout shift.
- 4
Re-measure
Confirm the LCP image is lighter and CLS-prone images now reserve their space.
Targeted at the metrics that matter
LCP detection
The audit identifies the likely Largest Contentful Paint candidate so you fix the right asset.
CLS signals
Missing width/height attributes are flagged per image.
Modern formats
WebP/AVIF cut the LCP image’s bytes 25–50% versus JPEG.
Right-sizing
Resizing to display size is usually the single biggest LCP improvement.
Render-blocking hints
The audit surfaces render-blocking CSS/JS and preload signals around images.
Estimated savings
See projected byte savings before you spend a single credit.
Frequently asked questions
Which Core Web Vitals do images affect?
Primarily Largest Contentful Paint (LCP) — the largest visible element is usually an image — and Cumulative Layout Shift (CLS), which images without declared width/height can cause as they load.
How do I improve my LCP score?
Find the LCP image, serve it in a modern format (WebP/AVIF), and resize it to its real display dimensions. Optimagio’s audit identifies the LCP candidate and the optimizer produces the lighter asset.
How do I stop images from causing layout shift?
Give every image explicit width and height attributes so the browser reserves space before the image loads. Optimagio’s audit flags images that are missing dimensions.
Start optimizing your images today
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