What are Core Web Vitals?
Core Web Vitals is a set of metrics that Google uses to determine how user-friendly a webpage is. The metrics measure a webpage’s responsiveness, stability, and load speed.
The metrics measured as part of the Core Web Vitals include:
- Interaction to Next Paint (INP)
- Largest Contentful Paint (LCP)
- Cumulative Layout Shift (CLS)
There is a fourth metric called the First Input Delay (FID). It was a Core Web Vital metric until March 2024 when it was replaced by the Interaction to Next Paint (INP). Google will end support for the First Input Delay on September 9, 2024.
Interaction to Next Paint (INP)
The Interaction to Next Paint (INP) measures the responsiveness of a webpage. It measures the duration between the moment a visitor clicks, taps, or uses the keyboard to interact with a resource on the page and the moment the page provides visual feedback indicating the interaction was successful.
The Interaction to Next Paint is measured for all interactions on the webpage. The duration of the longest interaction is then reported in the Core Web Vitals as the responsiveness of the entire page. You should keep it at 200 milliseconds or less.
Largest Contentful Paint (LCP)
The Largest Contentful Paint (LCP) measures how quickly the page loads. It measures the duration between the moment the webpage begins loading and when the largest image or longest paragraph is loaded. You should keep it at less than 2.5 seconds.
Cumulative Layout Shift (CLS)
The Cumulative Layout Shift (CLS) measures the visual stability of a webpage. This is how much the content on the page shifts as the text, images, and other webpage resources load. You should keep it at 0.1 or less.
Are Core Web Vitals a Ranking Factor?
The Core Web Vitals are one of the metrics that Google uses to determine the page experience signal of a web page. The page experience signal is a Google ranking factor.
Other page experience metrics include:
- Usage of HTTPS
- Mobile-friendliness
- Presence of intrusive interstitials