Spoke
Core Web Vitals
Three metrics with published thresholds, measured on real visits rather than a test you ran once. No interpretation needed. You either meet them or you don't.
Every threshold here is published by Google and recorded in our ledger with the date we checked it.
This is the rare corner of the field with published numbers.
No interpretation required, no practitioner consensus to weigh up. The thresholds are stated. Your site meets them or it doesn't.
What are the Core Web Vitals thresholds?
Largest Contentful Paint is good at 2.5 seconds or under. Interaction to Next Paint at 200 milliseconds or under. Cumulative Layout Shift at 0.1 or under. Each is assessed at the 75th percentile of real page loads, split across mobile and desktop.
A page passes only if all three are in the good range. Excellent on two and poor on the third is a fail.
Largest Contentful Paint is rated good at 2.5 seconds or less, measured at the 75th percentile of page loads and segmented across mobile and desktop.
Interaction to Next Paint is rated good at 200 milliseconds or less, measured at the 75th percentile.
INP became a stable Core Web Vital in 2024, replacing First Input Delay.
Cumulative Layout Shift is rated good at 0.1 or less, measured at the 75th percentile.
Why your test disagrees with your assessment
Most common source of confusion here, and it has a simple explanation. They measure different things.
A lab test runs once. One machine, one connection, usually a warm cache and no tag manager firing. Field assessment aggregates real visits — old phones, bad connections, markets with slow networks, every script that actually runs.
The percentile is the other half of it. Assessment at the 75th percentile means roughly a quarter of real visits can be worse than your number. Optimize for the median and you'll still fail.
Rule of thumb: use lab tools to diagnose. Never to conclude. Conclude from field data.
What each one is telling you
Largest Contentful Paint asks when the main content showed up. Failures usually come from a slow server, render-blocking resources, or a hero image that's unoptimized or found too late.
Interaction to Next Paint asks how fast the page responds when somebody touches it. Failures are almost always JavaScript holding the main thread. It replaced First Input Delay, which only measured the first interaction and was far more forgiving.
Cumulative Layout Shift asks whether things jump around while somebody's reading. Failures come from images with no dimensions, injected banners, and fonts loading late. Cheapest of the three to fix and the most infuriating to experience.
The honest weighting
These are a ranking input, and a modest one.
A fast page with weak content doesn't outrank a slow page that has the answer. Anybody promising you rankings from a performance project is selling the wrong thing.
The better argument is the direct one. Delays and jumping layouts cost you the visit whether or not anything ranks differently. And as more traffic arrives through AI citations — fewer visits, more deliberate ones — losing one to a janky page costs more than it used to.
More in Technical SEO
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Crawling and indexing are two different things, and a page can fail at either one. Most diagnosis goes wrong by treating them as a single step.
Architecture & URLs
How your pages are organized decides how they get found, how authority moves between them, and whether anyone can tell what the site is about. URLs are the visible shape of that decision.
Sitemaps & robots
These two files are where confident wrong advice concentrates, probably because they look simple enough that nobody bothers checking the documentation.
Structured data
Markup won't rank your page and won't make a claim true. Its job is to state outright what a machine would otherwise have to work out by guessing.
AI crawler access
Letting AI crawlers read your site is a real decision with a real trade-off. Most advice about it mixes up controls that do completely different jobs.
JavaScript & rendering
Google can render JavaScript" is true, and it gets used to justify architectures that cause real problems. The useful questions are when rendering happens, how reliably, and who else is looking.