pbserum.com website review

59 files are served with short cache lifetimes, so returning visitors download them again (9.1 MB).

17 images could be 7.6 MB smaller with modern formats (WebP or AVIF) and sizes that fit a phone screen. Google estimates it would make the page about 4.3 s faster on a phone.

About 330 KiB of JavaScript is downloaded but never used on this page. Google estimates it would make the page about 1.5 s faster on a phone.

Your mobile performance score is 54 (desktop: 58). Pages that score under 90 lose visitors before the first paint.

8 third-party services load with your homepage (Google Tag Manager, Cookiebot and Facebook and others), adding 868 KiB and 772 ms of main-thread time.

12 files block the first paint until they finish downloading. Deferring or inlining them could save about 800 ms.

Google Tag Manager costs a phone 374 ms of main-thread work and 528 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.

Cookiebot costs a phone 253 ms of main-thread work and 78 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.

7 long tasks block the main thread while loading, the longest for 163 ms. During a long task the page ignores taps.

Polyfills for old browsers add 46 KiB JavaScript that modern phones do not need.

About 12 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.

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 4.6 s for the largest content to appear (75th percentile). Good is under 2.5 s.

Real visitors see the first content after 3.9 s (75th percentile). Good is under 1.8 s.

Real visitors wait 3.4 s for your server to start answering (75th percentile). Good is under 800 ms.

Your largest element takes 12.6 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 35.6 s. Good is under 3.8 s.

Visually, the page fills in at 12.3 s (Speed Index). Good is under 3.4 s.

The first text or image appears after 2.4 s on a phone. Good is under 1.8 s.

Scripts block taps and scrolling for 370 ms in total while the page loads. Good is under 200 ms.

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

Over the last 25 four-week periods to 2026-10-17, real Chrome visitors' tap response (inp) went from 84 ms to 83 ms at the 75th percentile (Chrome UX Report (opens in a new tab) history).

Over the last 25 four-week periods to 2026-10-17, real Chrome visitors' largest content (lcp) went from 5.4 s to 4.8 s at the 75th percentile (Chrome UX Report (opens in a new tab) history).

Your homepage downloads 9.7 MB in 84 requests on a phone: images 8.6 MB (30), scripts 1.0 MB (29) and fonts 49 KiB (2). Under 2 MB keeps phones on slow connections fast.

9 images weigh 7.8 MB together. On a phone connection a single image that size takes seconds.

3 images are downloaded at several times the size a phone draws them, for example doctors.png at 1,000 px wide, shown at 250 px. Resized copies would save about 772 KiB.

17 images (8.5 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.

16 images further down the page (7.5 MB) download before anyone scrolls to them. Adding loading="lazy" lets the first screen load first.

By the Sustainable Web Design model, a visit to your homepage emits about 2.76 g of CO₂e: 330.7 kg a year at 10,000 visits a month. It scales with page weight, so every byte cut lowers it.

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

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

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

Documents must have <title> element to aid in navigation: 1 element on the page fails this check, rated serious by axe-core.

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

Landmarks should have a unique role or role/label/title (i.e. accessible name) combination: 1 element on the page fails this check, rated moderate by axe-core.

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

1 form field has no label, so screen readers announce an empty box and autofill guesses.

Your page has no <title>, so Google has to invent the blue link in search results.

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

2 links have no real href, so search engines can't follow them.

The homepage links to 65 pages on pbserum.com and 8 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://pbserum.com/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://pbserum.com/enzymes, https://pbserum.com/products-ranges/smartker, https://pbserum.com/products-ranges/specific, https://pbserum.com/products-ranges/plus, https://pbserum.com/products-ranges/ha and https://pbserum.com/products-ranges/ha-corrector and 9 others have no <title>, so Google invents the link text in results.

https://pbserum.com/blog/pbserum-inaugurates-the-bioremodeling-era-at-imcas-paris-2026 and https://pbserum.com/blog/solutions-for-hydration-deficiency-in-dry-skin-during-winter use the same meta description. A description written for each page earns more clicks.

https://pbserum.com/about-us has no <h1> headline, so visitors and search engines get no clear main topic.

We fetched 15 pages linked from your homepage (of 24 found) and read each the way a search engine does.

8 of 29 tappable elements near the top of the page are smaller than 24 px, hard to hit with a thumb.

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

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

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 669 words of visible text.

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

Opening the homepage sets 11 cookies (measured from a US location before any click).

Loading the homepage contacts 13 hosts run by other companies (fonts, scripts, analytics, ads), each of which sees the visitor's IP address.