15 JUL 2026

Website check-up: the 7 metrics that matter

Website check-up: seven metrics in a single health score from 0 to 100

“Do you think our site is in good shape?” It’s the question half our calls start with, and the serious answer isn’t “yes” or “no”: it’s “depends what you measure.” A beautiful site can be painfully slow; a lightning-fast one can be invisible to Google; one that’s perfect for Google can turn away one person in ten over an accessibility problem. Running a website check-up means looking at it on several fronts at once, with numbers, not by eye. Here are the seven metrics that really matter, and how to read them without becoming a technician.

Why a single number isn’t enough (and seven are).

A single score reassures, but it misleads. “PageSpeed 92” says something about speed and nothing about privacy, accessibility or AI readiness. That’s why a serious check-up doesn’t look at one thing: it lines up seven dimensions and weights them, so you see at a glance where the site is solid and where it loses points — and which problems are worth fixing first.

The seven check-up metrics — performance, SEO, accessibility, best practices, privacy, AI readiness, CO₂ — and the health-score bands — The seven metrics and the health-score bands (0–49 critical, 50–74 room to improve, 75–89 good, 90+ excellent). Four dimensions come from the Google PageSpeed API; three — privacy, AI readiness and CO₂ — are our own checks. Performance weighs the most (25), CO₂ the least (5).

The four metrics that come from Google.

Four of the seven metrics aren’t our opinion: they come from the Google PageSpeed API, the same one that powers pagespeed.web.dev, queried in mobile mode because that’s the version Google ranks you by.

aPerformance: how fast the page becomes usable on a phone. It’s the metric that weighs the most, and the one that decides whether visits stay or bolt.

bTechnical SEO: whether titles, structure and missing data are getting in the way of indexing.

cAccessibility: contrast, labels, heading structure — the barriers that since 2025 are also a legal requirement.

dBest practices: correct use of HTTPS, images, a clean console and the small signs of technical hygiene.

Web Vitals, Google’s definition →

The three metrics we add ourselves.

The other three we calculate directly, reading the site as a visitor would. Privacy compliance we read from the HTML (banner, notices, trackers firing before consent); AI readiness from four signals — llms.txt, AI-crawler access, structured data, sitemap; the CO₂ footprint from the page’s real weight, using the Sustainable Web Design model. These are indicative checks, and we say so: the privacy check isn’t legal advice, and the score doesn’t promise a position on Google. It’s a precise technical snapshot, not a sales promise.

How to read the health score.

The health score is the weighted average of the seven metrics, and it reads like a traffic light: 90 and up you’re in the green band, 75 to 89 is good, 50 to 74 there’s real room to improve, below 50 is critical and becomes the priority. Two caveats: a high score doesn’t mean “first on Google” — it means sound technical foundations; and if a metric comes back “N/A,” it’s usually not a fault on your side, but a saturated server or an automated read that was refused.

The best part is that you can measure all this yourself, free and in under a minute, by pasting in the site’s address. The full report, page by page, comes as a PDF; and if the check-up shows the technical foundation is worth rebuilding, the redesign starts there — from the numbers, not from a hunch.

Run the full check-up, free and with no sign-up →

If the foundation needs rebuilding: redesign and migration →

Sources.

The figures and claims in this article come from here. These are primary sources, not summaries: open them and check for yourself.

web.dev — Web VitalsThe definition of the speed and experience metrics that weigh most in the check-up.
Google — helpful, reliable content (E-E-A-T)The official guide to what Google considers quality: it’s the backdrop to the SEO dimension.
WCAG 2 — W3C/WAI overviewThe standard behind the accessibility measure, now also a legal requirement in the EU.
Sustainable Web Design — emissions estimateThe model we use to calculate the CO₂ footprint from the real page weight.
Chrome UX Report (CrUX)Google’s field data on real users, the basis of the speed metrics.

Run your site’s full check-up now — free →