What is PLS by device pixel ratio
PLS by device pixel ratio segments Perceived Load Speed (PLS) based on the device’s screen density — the ratio between physical pixels and device-independent pixels (DIPs). Common values include 1x, 1.25x, 2x, and 3x.
Devices with higher pixel ratios typically have sharper displays (like Retina screens) and are often higher-end. However, they also require more resources to render content crisply, which can impact how quickly the page feels loaded.
PLS (Perceived Load Speed) measures how fast the full page feels visually ready from a real user’s perspective, and viewing this by pixel ratio reveals how screen density affects that perception.
Healthy PLS by device pixel ratio sample
Should you worry
If all pixel ratio groups — from low-DPI to high-DPI — have similar or healthy PLS values, it means your site adapts well across screen types. That’s a good sign for responsive design and asset optimization.
If, however, certain pixel ratios (especially higher ones like 3x) consistently show slower PLS, it could mean your high-res assets or layout scaling are overloading devices with dense screens.
Unhealthy PLS by device pixel ratio sample
A poor experience may appear for users on 2x or 3x displays, indicating that images, videos, or effects served to those screens are too heavy or slow to load. This leads to a delayed perception of page readiness, especially on mid-tier devices trying to render high-DPI content.
Resolving unhealthy PLS by device pixel ratio
Go-to action plan to resolve an unhealthy PLS by device pixel ratio:
Ask Uxi to analyze your PLS by device pixel ratio and suggest improvements.
Use Filters to cross-analyze pixel ratio with device memory or CPU cores to identify if mid-range hardware is struggling with high-DPI rendering.
Simulate LCP of the suspected lens to see if fixing it will resolve the PLS by device pixel ratio. If yes, this is where the resolution focus should be.
Use an automated optimization tool like Navigation AI to improve your PLS by device pixel ratio.
Once you’ve improved PLS, set an alert to be the first to know if it starts worsening again.
Try it yourself
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