Introduction to LCP
Largest Contentful Paint (LCP) is one of the three Core Web Vitals and a key measure of how quickly your site feels fast. At Uxify, we use LCP as a key checkpoint for diagnosing visual load performance.
LCP marks the point in the page load timeline when the largest visible element in the viewport finishes rendering. This is typically an image, video thumbnail, or a large block of text like a heading. Since it usually represents the main content of the page, it’s often the moment users start to engage.
Healthy LCP
To deliver a fast experience, the 75th percentile (P75) of Largest Contentful Paint (LCP) should be under 2.5 seconds. This means 75% of your real users see the main content rendered within that time. Below is how Uxify categorizes LCP performance:
LCP Range | Status |
0 – 1.5s | Excellent |
1.5 – 2.5s | Good |
2.5 – 4.0s | Needs Improvement |
4.0s and above | Poor |
How LCP matters
Two words: users and Google. Let’s start with your users. If that big, beautiful image or crucial text takes forever to load, people might hit the back button faster than you can say “bounce rate”. A speedy LCP keeps them hooked, making your site feel responsive and welcoming.
Then there’s Google, the search engine overlord. LCP is part of its Core Web Vitals, a set of metrics it uses to judge how user-friendly your site is. A sluggish LCP? That could nudge you down the search rankings, making it tougher for potential customers to find you. In short: better LCP = happier users + higher visibility. Win-win!
Top 3 reasons for failing LCP
Here are three of the most common and actionable reasons we see for high LCP in Uxify Experience:
Inefficient or missing cache layer
Many sites we monitor have missing or poorly set up caching, with cache hit ratios as low as 20%. Caching is no longer optional, every site needs it. It is recommend keeping your cache hit ratio at 90% or as high as possible to keep fast Time to First Byte. You can easily detect this in the following Uxify LCP lenses: LCP breakdown, LCP by TTFB.
Slow regions
Even if your overall TTFB is fast, some regions may still experience delays. You can quickly detect this using the following Uxify LCP lenses: LCP by country, LCP by US State.
Third-parties
Certain third-parties do have LCP impact. You can detect this in the following Uxify LCP lenses: LCP breakdown, LCP by cookie name, LCP with ad blocker on/off, LCP by third party
You can use 80+ LCP lenses in Uxify Experience to find your website top reasons. It is presented on single dashboard view, so you know exactly where to focus. Once identified, you can improve the LCP user experience using Navigation AI.
Comparison to Perceived Load Speed (PLS)
While LCP measures a single element, Perceived Load Speed (PLS) looks at when the page feels loaded from a user’s point of view — considering multiple major elements and overall completeness.
In many cases, LCP happens before PLS. But if the LCP element is small or misleading (e.g., a banner), it can report as “fast” while the page still looks half-finished. That’s why we recommend tracking both.