congstar.de website review

The page goes through 1 redirect before it starts loading, costing about 8.2 s. Link and advertise the final URL directly.

About 726 KiB of JavaScript is downloaded but never used on this page. Google estimates it would make the page about 2.0 s faster on a phone.

11 files block the first paint until they finish downloading. Deferring or inlining them could save about 2.5 s.

Your mobile performance score is 43. Under 50 is Google's “poor” band: many phone visitors leave before the page is usable.

39 files are served with short cache lifetimes, so returning visitors download them again (724 KiB).

Kameleoon costs a phone 265 ms of main-thread work and 249 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.

A phone's processor spends 2.4 s on main-thread work while loading, 1.2 s of it running JavaScript. Above 2 s, taps and scrolls feel sluggish.

Usercentrics CMP costs a phone 168 ms of main-thread work and 511 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.

6 third-party services load with your homepage (Kameleoon, Usercentrics CMP and Adform and others), adding 929 KiB and 460 ms of main-thread time.

7 long tasks block the main thread while loading, the longest for 184 ms. During a long task the page ignores taps.

Polyfills for old browsers add 55 KiB JavaScript that modern phones do not need.

42 KiB could be saved by minifying JavaScript.

About 37 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.

3 KiB could be saved by minifying CSS.

The first text or image appears after 7.4 s on a phone. Good is under 1.8 s.

Your largest element takes 7.4 s to render on a phone. Google's threshold for “good” is 2.5 s. The largest element is the text “z. B. mit congstar Zuhause 100 Flex 100 Mbit/s für 36 € mtl.”.

The page becomes fully interactive after 16.5 s. Good is under 3.8 s.

Visually, the page fills in at 7.4 s (Speed Index). Good is under 3.4 s.

The layout shifts by 0.173 while loading, so content jumps under the reader's thumb. Good is under 0.1.

Scripts block taps and scrolling for 345 ms in total while the page loads. Good is under 200 ms.

1 image 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 134 ms to 137 ms at the 75th percentile (Chrome UX Report (opens in a new tab) history).

Your homepage downloads 2.5 MB in 133 requests on a phone: scripts 1.8 MB (76), fonts 253 KiB (11) and other files 160 KiB (19). Under 2 MB keeps phones on slow connections fast.

By the Sustainable Web Design model, a visit to your homepage emits about 0.70 g of CO₂e: 83.4 kg a year at 10,000 visits a month. It scales with page weight, so every byte cut lowers it.

All page content should be contained by landmarks: 38 elements on the page fail this check, rated moderate by axe-core.

The page has no <main> landmark, so screen-reader users cannot jump straight to the content.

Page should contain a level-one heading: 1 element on the page fails this check, rated moderate by axe-core.

Google's crawler is blocked from indexing this page.

1 link use generic text like “click here” or “learn more”, which tells Google nothing about the page behind it.

Open Graph is missing og:title and og:description, so shared links fall back to guesses.

The homepage links to 174 pages on congstar.de 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 /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.

/handytarife, /handytarife/smartphone-tarife-im-vergleich, /handytarife/allnet-flat-tarife/allnet-flat-l, /handytarife/allnet-flat-tarife/allnet-flat-m and /handytarife/allnet-flat-tarife/allnet-flat-s took over 3 s to send their HTML from our server.

We fetched 15 pages linked from your homepage (of 116 found) and read each the way a search engine does.

3 errors were logged to the browser console while the page loaded, for example “Access to XMLHttpRequest at 'https://cdn.congstar.de/libraries/@congstar/congstar-fair-ui/2.62.1/style.css' from origin…”.

Large scripts ship without source maps.

No Content-Security-Policy header, the main browser-side defence against injected scripts.

HSTS is set, but max-age is 356 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.

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

congstar.de 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.

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

No analytics or tag manager detected in the HTML, so you can't measure whether any of these fixes work.

No phone number or email link on the homepage, so ready-to-buy visitors have one fewer way to reach you.

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

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 390 words of visible text.

DMARC is set to p=none, so mail pretending to be congstar.de 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.

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

Loading the homepage contacts 4 hosts run by other companies (fonts, scripts, analytics, ads), each of which sees the visitor's IP address.