4endurance.si website review

A phone's processor spends 4.9 s on main-thread work while loading, 2.2 s of it running JavaScript. Above 2 s, taps and scrolls feel sluggish.

8 third-party services load with your homepage (Google Tag Manager, Facebook and Klaviyo and others), adding 1.2 MB and 1.2 s of main-thread time.

Your mobile performance score is 54 (desktop: 75). Pages that score under 90 lose visitors before the first paint.

5 files block the first paint until they finish downloading. Deferring or inlining them could save about 600 ms.

About 441 KiB of JavaScript is downloaded but never used on this page. Google estimates it would make the page about 150 ms faster on a phone.

16 images could be 448 KiB smaller with modern formats (WebP or AVIF) and sizes that fit a phone screen.

Google Tag Manager costs a phone 366 ms of main-thread work and 310 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.

About 48 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.

Facebook costs a phone 290 ms of main-thread work and 227 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.

Klaviyo costs a phone 257 ms of main-thread work and 372 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.

13 files are served with short cache lifetimes, so returning visitors download them again (292 KiB).

The page has 2,695 HTML elements. Above 1,500, rendering and every interaction get slower on phones.

19 long tasks block the main thread while loading, the longest for 227 ms. During a long task the page ignores taps.

Polyfills for old browsers add 30 KiB JavaScript that modern phones do not need.

19 KiB could be saved by minifying JavaScript.

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.

The page becomes fully interactive after 25.6 s. Good is under 3.8 s.

Your largest element takes 6.5 s to render on a phone. Google's threshold for “good” is 2.5 s. The largest element is the image.

Scripts block taps and scrolling for 595 ms in total while the page loads. Good is under 200 ms.

Visually, the page fills in at 5.5 s (Speed Index). Good is under 3.4 s.

The first text or image appears after 2.5 s on a phone. Good is under 1.8 s.

18 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 110 ms to 130 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 1.4 s to 1.5 s at the 75th percentile (Chrome UX Report (opens in a new tab) history).

Your homepage downloads 5.2 MB in 286 requests on a phone: other files 2.1 MB (133), scripts 1.5 MB (85) and images 1.3 MB (48). Under 2 MB keeps phones on slow connections fast.

18 images (1.9 MB) are 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.

8 images further down the page (694 KiB) download before anyone scrolls to them. Adding loading="lazy" lets the first screen load first.

6 images are downloaded at several times the size a phone draws them, for example 4Endurance-produktne-kategorije-topilci-mascob.webp at 800 px wide, shown at 173 px. Resized copies would save about 366 KiB.

By the Sustainable Web Design model, a visit to your homepage emits about 1.47 g of CO₂e: 176.3 kg a year at 10,000 visits a month. It scales with page weight, so every byte cut lowers it.

6 buttons have no accessible name, so screen readers announce just “button”.

2 elements use ARIA attributes their role does not allow, which confuses screen readers.

27 text elements don't have enough contrast against the background to read easily, especially outdoors on a phone.

5 tap targets are too small or too close together to hit reliably with a finger.

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

All page content should be contained by landmarks: 5 elements on the page fail this check, rated moderate by axe-core.

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

Alternative text of images should not be repeated as text: 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.

Structured data found (BreadcrumbList, OnlineStore and Organization) but with 1 problem, for example “Organization: url points at a different host (https://4endurance.com)”.

The homepage links to 209 pages on 4endurance.si and 37 external pages.

We fetched 15 pages linked from your homepage (of 68 found) and read each the way a search engine does.

1 image failed to load on a phone, for example https://4endurance.si/.

On a 390 px-wide phone the page scrolls sideways, a sign that something is wider than the screen.

The page uses 1 deprecated browser API that will stop working in future browsers (“Synchronous `XMLHttpRequest` on the main thread is deprecated because of its detrimental effects to…”).

3 errors were logged to the browser console while the page loaded, for example “Logged exception (this may happen if you have tried to edit the code without properly adjusting the JavaScript): Cannot…”.

1 image is displayed at the wrong aspect ratio, so it looks stretched or squashed.

1 image is served at too low a resolution for sharp phone screens.

1 link from your homepage to your own site is broken, for example https://4endurance.si/pages/uec2026 (404).

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.

4endurance.si 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.

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

We found no call-to-action buttons or links (such as “Book a demo” or “Get a quote”) anywhere on the homepage.

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

The homepage shows no opening hours. If customers visit or call, show when.

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 711 words of visible text.

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 Google Ads, Google Analytics, Google Tag Manager, Hotjar and Klaviyo and 1 more (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 16 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 36 hosts run by other companies (fonts, scripts, analytics, ads), each of which sees the visitor's IP address.