What is PLS by CPU performance
PLS by CPU performance shows how Perceived Load Speed (PLS) varies across devices with different CPU capabilities. It reveals whether lower-tier processors are impacting how fast the page feels to load.
PLS is Uxify’s real-user metric designed to measure the moment a page feels visually complete — when users perceive it as ready for interaction. It’s based on actual user experiences, not synthetic assumptions.
Devices with weaker CPUs — such as entry-level phones or older laptops — may struggle to process JavaScript, render visuals, and complete layout tasks efficiently. This can delay the moment when the page appears fully ready to the user, even if network conditions are decent.
Healthy PLS by CPU performance sample
Should you worry
A healthy distribution shows all CPU tiers (high, mid, low) delivering similar PLS values — ideally in the green zone. This means your site is performant and lightweight enough to deliver a good experience even on resource-constrained devices.
If users with low or mid-tier CPUs experience significantly slower PLS, they may be waiting longer to see a usable page. This delay can frustrate users, especially on mobile, and lead to higher drop-offs before engagement or conversion.
Unhealthy PLS by CPU performance sample
Slower PLS for low-tier CPUs often indicates heavy frontend logic, large layout shifts, or render-blocking scripts. These issues may not appear in lab tests or on high-end devices — making real-user insights critical.
Resolving unhealthy PLS by CPU performance
Go-to action plan to resolve an unhealthy PLS by CPU performance:
Ask Uxi to analyze your PLS by CPU performance and suggest improvements.
Use Filters to narrow down to users on slower CPUs and identify which pages or components are problematic.
Simulate LCP of the suspected breakdown to see if fixing it will resolve the PLS by CPU performance. If yes, this is where the resolution focus should be.
Use an automated optimization tool like Navigation AI to improve your PLS by CPU performance.
Once you’ve improved PLS, set an alert to be the first to know if it starts worsening again.
Try it yourself
Discover how your website performs with real user data.