What is Largest Contentful Paint (LCP) and how to improve it
If you’ve run a speed test, you’ve seen “LCP.” It’s the metric that matters most for how fast your store feels — and it’s a Google ranking factor.
What LCP measures
Largest Contentful Paint is the time until the biggest visible element on the page — usually your hero image or main product photo — has loaded. It’s a proxy for “when does this page feel ready?”
What’s a good LCP?
- Good: under 2.5 seconds
- Needs work: 2.5–4 seconds
- Poor: over 4 seconds
These thresholds are measured on mobile, which is where most ecommerce traffic is. Many stores sit at 4–8 seconds on a phone.
How to improve it
Because LCP is usually your hero/product image, most fixes are about that element:
- Compress and right-size the LCP image. Don’t serve a 3000px image into a 600px slot.
- Use modern formats (WebP/AVIF).
- Preload the hero image so the browser fetches it early.
- Don’t lazy-load the LCP image — lazy-loading is for below-the-fold content only.
- Cut render-blocking scripts and fonts that delay the paint.
- Use a fast theme and Shopify’s image CDN.
Measure yours
The free page speed test reads your real LCP (and overall score) from your URL — no guessing — and shows what slow speed costs you. For the fixes step by step, see how to speed up your Shopify store. For every leak in one place, there’s Revyfix.