Guides Jul 30, 2026 7 min read
Web Vitals, explained for the people who write the pages
Three numbers decide whether Google thinks your page is fast. None of them are the number your developer quotes. A plain-language guide to LCP, INP, and CLS.
Mara Lindqvist
Ask a developer how fast a page is and you will get a load time. Ask Google and you will get three numbers with initials, measured from real visitors, and a verdict of good, needs improvement, or poor. This is a guide to those three numbers written for the people who own the pages rather than the people who build them.
LCP: when the big thing shows up
Largest Contentful Paint is the moment the biggest element in the first screen finishes rendering. On a landing page that is nearly always the hero image or the headline. Under 2.5 seconds is good. The usual culprit is a hero image that is much larger than it needs to be, or a font that blocks the headline from painting until it downloads.
INP: how the page feels when you touch it
Interaction to Next Paint measures the delay between a tap or click and the screen changing in response, across the whole visit. Under 200 milliseconds is good. When it is bad, the reason is almost always JavaScript doing too much on the main thread: a chat widget, a tag manager, three analytics scripts, or an animation library that is busy when the visitor tries to press the button.
CLS: does the page jump
Cumulative Layout Shift is the amount the page moves around while it loads. You have felt this: you go to tap a link and an ad pushes it down at the last moment. Under 0.1 is good. Images without a declared size and late-loading banners are the usual cause.
Why we show one score
Current collects all three from real visits and folds them into a single experience score from 0 to 100, per page and for the site as a whole. The score exists so that a page can be compared with another page and last week can be compared with this week, without anyone needing to remember what INP stands for. When it drops, the page that dropped it is at the top of the list.
If you only remember one thing: every third-party script you add is a tax on INP, and the tax is paid by the visitor who was about to buy.
More from the blog
- Aug 28, 2026 Why we count revenue, not pageviews Every analytics tool tells you how many people came. Almost none tell you which of them paid. That gap is the whole reason Current exists.
- Aug 12, 2026 Keeping the script under one kilobyte A tracking script is a tax on every page you ship. Here is how ours stays at 812 bytes, what we left out, and why the size is a promise rather than a boast.
- Jul 14, 2026 Current reached $5K in monthly revenue Nine months after launch, two founders, no funding. What worked, what did not, and the exact channels that paid for it, from our own dashboard.