Core Web Vitals in New Zealand, 2026
By Malte Warncke, web performance engineer. Published . Data collected from 28 September 2026 to 8 October 2026.
62% of popular New Zealand websites fail Google's Core Web Vitals. I checked Chrome's real-user data for the 1,033 most-visited .co.nz domains. 715 of them get enough traffic to be measured, and 440 of those load too slowly, react too slowly or jump around too much for more than a quarter of their visits.
How popular .co.nz websites score
A site fails when Google's real-user data puts it over the "good" limit for at least one of the three Core Web Vitals.
| Core Web Vital | Good is | Sites over it |
|---|---|---|
| Largest Contentful Paint: how fast the main content appears | ≤ 2.5 s | 39% (278 of 715) |
| Interaction to Next Paint: how fast the page reacts to a tap | ≤ 200 ms | 34% (229 of 677) |
| Cumulative Layout Shift: how much the layout jumps | ≤ 0.1 | 23% (165 of 715) |
| Core Web Vitals overall | all three good | 62% (440 of 715) |
The most-visited .com websites do no better: 61% of the 322 I checked fail as well.
What the slow sites have in common
I also audited 164 sites in full (132 of them .co.nz). I picked them because they looked slow, so these numbers describe slow sites, not all sites.
- The main image waits, then loads fast. On the median site, the browser waited 1.3 seconds before it even started downloading the main image. The download itself took 0.17 seconds. A wait like that usually means the browser finds the image late, for example because it is lazy-loaded, set in CSS or added by JavaScript. (146 sites whose main content is an image.)I explain the causes and the fixes in my guide Why your LCP image loads late.
- Third-party scripts pile up. The median site loads 14 third-party services, such as analytics, ads, chat and A/B testing, with 1.3 MB of their JavaScript. 86% use a tag manager. (153 sites.)
- Pages are heavy. The median page weighs 5.8 MB on mobile and scores 31 out of 100 in Google's mobile PageSpeed test. (148 sites.)
- Servers answer slowly. On the median site, the first byte of the page arrives after 0.98 seconds for a typical (75th percentile) mobile visit. Google's "good" is 0.8 seconds or less. (160 sites.)
A performance audit checks each of these on your own site and puts the fixes in order: what my website performance audit covers.
What crawlers see before JavaScript runs
Google can run a page's JavaScript, but crawlers that don't see only the HTML the server sends. In that HTML, across the 150 audited sites I could check:
- 52% have no main heading (h1).
- 53% have no structured data (JSON-LD).
- 35% have no canonical tag.
- 52% have no image for link previews (og:image).
- 20% stop visitors from zooming in on a phone.
How I collected the data
- Which sites: the 1,048 most-visited .co.nz domains in the Tranco list (opens in a new tab), a research ranking of popular websites. The list was refreshed between my scan runs, so that adds up to 1,033 different domains.
- Real-user data: Google's Chrome UX Report (opens in a new tab), the same data behind PageSpeed Insights and Search Console. Values are the 75th percentile of the last 28 days, for the homepage where Google has page-level data and for the whole site otherwise. Mobile, unless a site only has desktop data.
- Thresholds: Google's "good" thresholds (opens in a new tab): LCP ≤ 2.5 s, INP ≤ 200 ms, CLS ≤ 0.1.
- Full audits: PageSpeed Insights, Lighthouse and the Chrome UX Report for each homepage, plus a check of the HTML it serves, from 16 September 2026 to 7 October 2026.
What this data can't tell you
- It covers popular sites only. 318 of the 1,033 domains had no real-user data (usually too little Chrome traffic) or redirected elsewhere, so they aren't counted.
- It looks at homepages. Product and article pages can be faster or slower.
- The full audits cover slow sites by design. A random sample of websites would look better.
- I don't name individual sites.
Is your website one of them?
Send me your URL and I'll check it against the same data, for free. Within 2 business days you get its biggest performance problems and 3 quick wins.