silumen.com website review

7 files block the first paint until they finish downloading. Deferring or inlining them could save about 1.1 s.

Your mobile performance score is 63. Pages that score under 90 lose visitors before the first paint.

8 third-party services load with your homepage (Google Tag Manager, Facebook and Clarity and others), adding 887 KiB and 800 ms of main-thread time.

27 images could be 776 KiB smaller with modern formats (WebP or AVIF) and sizes that fit a phone screen.

About 264 KiB of JavaScript is downloaded but never used on this page. Google estimates it would make the page about 300 ms faster on a phone.

About 38 KiB of CSS is downloaded but never applied on this page. Google estimates it would make the page about 300 ms faster on a phone.

A phone's processor spends 3.3 s on main-thread work while loading, 1.4 s of it running JavaScript. Above 2 s, taps and scrolls feel sluggish.

Google Tag Manager costs a phone 286 ms of main-thread work and 360 KiB of downloads while your page loads. Loading it after the page is usable, or only on the pages that need it, takes that off the critical path.

The page has 2,642 HTML elements. Above 1,500, rendering and every interaction get slower on phones.

10 files are served with short cache lifetimes, so returning visitors download them again (241 KiB).

7 long tasks block the main thread while loading, the longest for 180 ms. During a long task the page ignores taps.

Polyfills for old browsers add 21 KiB JavaScript that modern phones do not need. Google estimates it would make the page about 50 ms faster on a phone.

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.

Your largest element takes 8.0 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 13.3 s. Good is under 3.8 s.

Over the last 25 four-week periods to 2026-10-31, real Chrome visitors' tap response (inp) went from 164 ms to 196 ms at the 75th percentile (Chrome UX Report (opens in a new tab) history).

Scripts block taps and scrolling for 423 ms in total while the page loads. Good is under 200 ms.

Visually, the page fills in at 4.1 s (Speed Index). Good is under 3.4 s.

Your homepage downloads 3.5 MB in 261 requests on a phone: images 1.4 MB (43), scripts 1.1 MB (96) and other files 760 KiB (104). Under 2 MB keeps phones on slow connections fast.

2_EN_1311895a-d94e-4e79-a516-397d9f7d762d.jpg is on the first screen but marked loading="lazy", so the browser waits before fetching it and the page looks finished later. Load it eagerly (and give it fetchpriority="high" if it is the main image).

By the Sustainable Web Design model, a visit to your homepage emits about 1.00 g of CO₂e: 120.5 kg a year at 10,000 visits a month. It scales with page weight, so every byte cut lowers it.

2 elements hidden from screen readers can still receive keyboard focus.

1 text element doesn't have enough contrast against the background to read easily, especially outdoors on a phone.

All page content should be contained by landmarks: 2 elements on the page fail this check, rated moderate by axe-core.

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

Elements with visible text labels do not have matching accessible names. (1 element).

The homepage links to 617 pages on silumen.com and 5 external pages.

There is no /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.

/en/pages/chantiers-hiver and /en/pages/simulateur-deconomies-led have no meta description, so Google writes the search snippet from whatever text it finds.

We fetched 15 pages linked from your homepage (of 195 found) and read each the way a search engine does.

1 image failed to load on a phone, for example https://bat.bing.com/action/0?ti=25057838&tm=gtm002&Ver=2&mid=ec2d5e8c-6616-44c4-9ecc-2f14cfa9bb27&bo=2&sid=4c7cfbb0db7411f1a8b37bc9afb98afd&vid=4c7d3000db7411f1b4c491bfded20037&vids=1&msclkid=N&pi=91.

1 error was logged to the browser console while the page loaded, for example “Failed to fetch”.

HSTS is set, but max-age is 91 days; one year is the recommended minimum.

No Referrer-Policy header, so full URLs can leak to the sites you link to.

No Permissions-Policy header to switch off camera, microphone and location for embedded content.

X-XSS-Protection is set to “1; mode=block”; the header is deprecated and can introduce bugs. Use 0 or remove it.

There is no /.well-known/security.txt telling researchers how to report a security problem to you.

silumen.com is registered until Nov 2026. If it lapses, the site and its email stop working and someone else can buy the name. Renew it, and turn on auto-renew.

silumen.com has no CAA record, so any certificate authority may issue a certificate for it. A CAA record naming your provider (for example letsencrypt.org) closes that door.

silumen.com's DNS answers are not signed. DNSSEC stops attackers forging them to send visitors or email elsewhere; most registrars switch it on in a click, though most sites still run without it.

On a phone, there is no call to action on the first screen: visitors have to scroll to find out what to do next.

Your homepage shows a street address but no LocalBusiness JSON-LD, so Google and AI assistants have to guess your address, hours and phone from the page text.

There is no link to Google or Apple Maps. A directions link is one tap for a phone visitor.

No guarantee or risk reducer (money-back, free trial, no credit card) is mentioned, which is often what tips a hesitant visitor.

The homepage carries about 790 words of visible text.

The page uses urgency cues (a countdown or limited-time wording).

DMARC is set to p=none, so mail pretending to be silumen.com is still delivered. Reports are on, so moving to quarantine is the next step.

Email authentication: SPF record 25 points, plus 15 when it ends in -all (10 for ~all); DMARC record 25, plus 25 for a reject policy (15 for quarantine); a DKIM key on a common selector 10.

Before a visitor clicks anything, the page loads Criteo, Google Ads, Google Analytics, Google Tag Manager and Meta Pixel and 2 mores (measured from a US location before any click). No consent tool was detected. Visitors from the EU, UK and several US states must be asked first.

Opening the homepage sets 17 cookies (measured from a US location before any click).

No known cookie consent tool loads with the page. Some sites build their own banner, and some only show one to visitors from the EU.

Loading the homepage contacts 26 hosts run by other companies (fonts, scripts, analytics, ads), each of which sees the visitor's IP address.