Report Summary

  • 34

    Performance

    Renders faster than
    55% of other websites

  • 74

    Accessibility

    Visual factors better than
    that of 41% of websites

  • 83

    Best Practices

    More advanced features
    available than in
    57% of websites

  • 90

    SEO

    Google-friendlier than
    69% of websites

vdi.nl

Ontwerp, installatie en beheer van techniek | Van Dorp

Page Load Speed

3.8 sec in total

First Response

506 ms

Resources Loaded

3.1 sec

Page Rendered

186 ms

vdi.nl screenshot

About Website

Visit vdi.nl now to see the best up-to-date Vdi content for Netherlands and also check out these interesting facts you probably never knew about vdi.nl

Energie besparen en uw installaties verduurzamen? Van Dorp biedt alle technische oplossingen in gebouwen. Neem contact op voor advies op maat.

Visit vdi.nl

Key Findings

We analyzed Vdi.nl page load time and found that the first response time was 506 ms and then it took 3.3 sec to load all DOM resources and completely render a web page. This is a poor result, as 55% of websites can load faster.

Performance Metrics

vdi.nl performance score

34

Measured Metrics

name

value

score

weighting

FCP (First Contentful Paint)

Value4.4 s

16/100

10%

LCP (Largest Contentful Paint)

Value10.4 s

0/100

25%

SI (Speed Index)

Value5.4 s

57/100

10%

TBT (Total Blocking Time)

Value490 ms

59/100

30%

CLS (Cumulative Layout Shift)

Value0.304

39/100

15%

TTI (Time to Interactive)

Value9.9 s

27/100

10%

Network Requests Diagram

vdi.nl

506 ms

jquery-1.9.1.js

687 ms

cycle2_plugin.js

494 ms

jquery.easing.min.js

8 ms

font-awesome.min.css

22 ms

Our browser made a total of 50 requests to load all elements on the main page. We found that 80% of them (40 requests) were addressed to the original Vdi.nl, 4% (2 requests) were made to Google-analytics.com and 4% (2 requests) were made to S.ytimg.com. The less responsive or slowest element that took the longest time to load (2 sec) belongs to the original domain Vdi.nl.

Page Optimization Overview & Recommendations

Page size can be reduced by 808.3 kB (23%)

Content Size

3.5 MB

After Optimization

2.7 MB

In fact, the total size of Vdi.nl main page is 3.5 MB. This result falls beyond the top 1M of websites and identifies a large and not optimized web page that may take ages to load. 40% of websites need less resources to load. Images take 2.6 MB which makes up the majority of the site volume.

HTML Optimization

-78%

Potential reduce by 14.5 kB

  • Original 18.5 kB
  • After minification 15.7 kB
  • After compression 4.0 kB

HTML content can be minified and compressed by a website’s server. The most efficient way is to compress content using GZIP which reduces data amount travelling through the network between server and browser. This page needs HTML code to be minified as it can gain 2.8 kB, which is 15% of the original size. It is highly recommended that content of this web page should be compressed using GZIP, as it can save up to 14.5 kB or 78% of the original size.

Image Optimization

-4%

Potential reduce by 113.5 kB

  • Original 2.6 MB
  • After minification 2.5 MB

Image size optimization can help to speed up a website loading time. The chart above shows the difference between the size before and after optimization. Vdi images are well optimized though.

JavaScript Optimization

-76%

Potential reduce by 446.1 kB

  • Original 590.4 kB
  • After minification 422.9 kB
  • After compression 144.4 kB

It’s better to minify JavaScript in order to improve website performance. The diagram shows the current total size of all JavaScript files against the prospective JavaScript size after its minification and compression. It is highly recommended that all JavaScript files should be compressed and minified as it can save up to 446.1 kB or 76% of the original size.

CSS Optimization

-82%

Potential reduce by 234.2 kB

  • Original 284.4 kB
  • After minification 279.3 kB
  • After compression 50.2 kB

CSS files minification is very important to reduce a web page rendering time. The faster CSS files can load, the earlier a page can be rendered. Vdi.nl needs all CSS files to be minified and compressed as it can save up to 234.2 kB or 82% of the original size.

Requests Breakdown

Number of requests can be reduced by 9 (18%)

Requests Now

49

After Optimization

40

The browser has sent 49 CSS, Javascripts, AJAX and image requests in order to completely render the main page of Vdi. We recommend that multiple CSS and JavaScript files should be merged into one by each type, as it can help reduce assets requests from 7 to 1 for JavaScripts and from 4 to 1 for CSS and as a result speed up the page load time.

Accessibility Review

vdi.nl accessibility score

74

Accessibility Issues

Names and labels

These are opportunities to improve the semantics of the controls in your application. This may enhance the experience for users of assistive technology, like a screen reader.

Impact

Issue

High

Buttons do not have an accessible name

High

Image elements do not have [alt] attributes

High

Links do not have a discernible name

Contrast

These are opportunities to improve the legibility of your content.

Impact

Issue

High

Background and foreground colors do not have a sufficient contrast ratio.

Navigation

These are opportunities to improve keyboard navigation in your application.

Impact

Issue

High

Heading elements are not in a sequentially-descending order

Best Practices

vdi.nl best practices score

83

Areas of Improvement

Trust and Safety

Impact

Issue

High

Does not use HTTPS

High

Includes front-end JavaScript libraries with known security vulnerabilities

Low

Ensure CSP is effective against XSS attacks

General

Impact

Issue

Low

Detected JavaScript libraries

High

Page has valid source maps

SEO Factors

vdi.nl SEO score

90

Search Engine Optimization Advices

Content Best Practices

Format your HTML in a way that enables crawlers to better understand your app’s content.

Impact

Issue

High

Image elements do not have [alt] attributes

Mobile Friendly

Make sure your pages are mobile friendly so users don’t have to pinch or zoom in order to read the content pages. [Learn more](https://developers.google.com/search/mobile-sites/).

Impact

Issue

High

Document uses legible font sizes

High

Tap targets are not sized appropriately

Language and Encoding

  • Language Detected

    NL

  • Language Claimed

    EN

  • Encoding

    UTF-8

Language claimed in HTML meta tag should match the language actually used on the web page. Otherwise Vdi.nl can be misinterpreted by Google and other search engines. Our service has detected that Dutch is used on the page, and it does not match the claimed English language. Our system also found out that Vdi.nl main page’s claimed encoding is utf-8. Use of this encoding format is the best practice as the main page visitors from all over the world won’t have any issues with symbol transcription.

Social Sharing Optimization

Open Graph description is not detected on the main page of Vdi. Lack of Open Graph description can be counter-productive for their social media presence, as such a description allows converting a website homepage (or other pages) into good-looking, rich and well-structured posts, when it is being shared on Facebook and other social media. For example, adding the following code snippet into HTML <head> tag will help to represent this web page correctly in social networks: