visilab.ch website review

110 files are served with short cache lifetimes, so returning visitors download them again (2.6 MB).

About 886 KiB of JavaScript is downloaded but never used on this page. Google estimates it would make the page about 2.6 s faster on a phone.

Your mobile performance score is 45 (desktop: 51). Under 50 is Google's “poor” band: many phone visitors leave before the page is usable.

A phone's processor spends 4.0 s on main-thread work while loading, 2.1 s of it running JavaScript. Above 2 s, taps and scrolls feel sluggish.

15 long tasks block the main thread while loading, the longest for 429 ms. During a long task the page ignores taps.

The page has 2,670 HTML elements. Above 1,500, rendering and every interaction get slower on phones.

5 third-party services load with your homepage (Google Tag Manager, Unbounce and New Relic and others), adding 390 KiB and 174 ms of main-thread time.

9 images could be 174 KiB smaller with modern formats (WebP or AVIF) and sizes that fit a phone screen.

Web fonts hide text while they load. Setting font-display: swap shows text immediately (about 100 ms).

Polyfills for old browsers add 27 KiB JavaScript that modern phones do not need. Google estimates it would make the page about 50 ms faster on a phone.

About 23 KiB of CSS is downloaded but never applied on this page.

Critical files load one after another instead of in parallel (3 chains). Preconnecting to key origins and preloading the hero image shortens the chain.

Scripts make the browser recalculate the layout repeatedly while the page loads, which wastes processor time on phones.

Real Chrome users on phones do not pass Google's Core Web Vitals on this page (28-day field data from the Chrome UX Report (opens in a new tab)). Google uses this in ranking.

Real visitors wait 5.6 s for the largest content to appear (75th percentile). Good is under 2.5 s.

Real visitors see the first content after 3.7 s (75th percentile). Good is under 1.8 s.

Real visitors wait 4.4 s for your server to start answering (75th percentile). Good is under 800 ms.

Your largest element takes 17.1 s to render on a phone. Google's threshold for “good” is 2.5 s. The largest element is the image.

The page becomes fully interactive after 18.4 s. Good is under 3.8 s.

Scripts block taps and scrolling for 959 ms in total while the page loads. Good is under 200 ms.

Visually, the page fills in at 7.2 s (Speed Index). Good is under 3.4 s.

Real visitors wait 278 ms for the page to respond to a tap (75th percentile). Good is under 200 ms.

For real visitors the layout shifts by 0.21 (75th percentile). Good is under 0.1.

The first text or image appears after 2.0 s on a phone. Good is under 1.8 s.

9 images have no width and height attributes, so the layout jumps as each one loads.

Over the last 25 four-week periods to 2026-10-24, real Chrome visitors' tap response (inp) went from 247 ms to 236 ms at the 75th percentile (Chrome UX Report (opens in a new tab) history).

Over the last 25 four-week periods to 2026-10-24, real Chrome visitors' largest content (lcp) went from 2.4 s to 2.3 s at the 75th percentile (Chrome UX Report (opens in a new tab) history).

Your homepage downloads 5.5 MB in 235 requests on a phone: images 2.1 MB (91), other files 2.0 MB (115) and scripts 1.1 MB (25). Under 2 MB keeps phones on slow connections fast.

4 images are downloaded at several times the size a phone draws them, for example Website2023_Magazine_Presbytie_ContentDetail_816x816_1.jpg at 816 px wide, shown at 151 px. Resized copies would save about 141 KiB.

7 images further down the page (366 KiB) download before anyone scrolls to them. Adding loading="lazy" lets the first screen load first.

1 image (33 KiB) is JPEG, PNG or GIF. The same pictures as WebP or AVIF are usually much smaller at the same quality, and every current browser shows them.

By the Sustainable Web Design model, a visit to your homepage emits about 1.55 g of CO₂e: 186.5 kg a year at 10,000 visits a month. It scales with page weight, so every byte cut lowers it.

1 button has no accessible name, so screen readers announce just “button”.

Interactive controls must not be nested: 1 element on the page fails this check, rated serious by axe-core.

5 images have no alt text, which hurts accessibility and image search.

17 visible links have no text or label, so screen readers cannot say where they go.

Users should be able to zoom and scale the text up to 500%: 1 element on the page fails this check, rated minor by axe-core.

Headings skip levels (h2 → h4), which makes the page harder to scan with a screen reader.

Your title is 101 characters, so Google will cut it off around 60: “VISILAB - Online Optician in Switzerland : Prescription Glasses, Sunglasses, Contact Lens…”.

Your meta description is 204 characters; Google truncates after about 160, so the end of your pitch is cut.

No Open Graph image (also missing: og:title, og:description), so links shared on LinkedIn, Slack or Facebook show no preview picture.

2 links use generic text like “click here” or “learn more”, which tells Google nothing about the page behind them.

1 link has no real href, so search engines can't follow it.

No twitter:card tag. X falls back to Open Graph, which is incomplete here.

The homepage links to 334 pages on visilab.ch and 3 external pages.

There is no Organization (or LocalBusiness) JSON-LD, so search engines and AI assistants have no machine-readable facts about who runs the site: its name, logo, profiles and contact details.

There is no https://www.visilab.ch/llms.txt, a short Markdown guide to your key pages for AI tools (llmstxt.org). It is optional and few AI tools read it yet, so treat it as a cheap extra.

https://www.visilab.ch/en/opticians and https://www.visilab.ch/en/appointments use the same meta description. A description written for each page earns more clicks.

https://www.visilab.ch/en/appointments has under 150 words in the HTML. Thin pages rarely rank; if the text loads with JavaScript, crawlers that don't run it see even less.

We fetched 15 pages linked from your homepage (of 176 found) and read each the way a search engine does.

The page uses 1 deprecated browser API that will stop working in future browsers (“Unload event listeners are deprecated and will be removed.”).

1 error was logged to the browser console while the page loaded, for example “Failed to load resource: the server responded with a status of 402 ()”.

Large scripts ship without source maps.

No testimonials, customer logos, ratings or customer counts on the homepage: nothing tells a new visitor that others already trust you.

There is no form on the homepage, so every lead has to click through to another page first.

The homepage carries about 432 words of visible text.

Before a visitor clicks anything, the page loads Google Tag Manager (measured from a US location before any click). A consent tool (CookieYes) is installed; check it blocks these until visitors agree where the law requires it.

Opening the homepage sets 3 cookies (measured from a US location before any click).

Loading the homepage contacts 8 hosts run by other companies (fonts, scripts, analytics, ads), each of which sees the visitor's IP address.