Tools & Wizards About Us

Report Summary

  • 33

    Performance

    Renders faster than
    53% of other websites

  • 84

    Accessibility

    Visual factors better than
    that of 56% of websites

  • 92

    Best Practices

    More advanced features
    available than in
    80% of websites

  • 83

    SEO

    Google-friendlier than
    46% of websites

ub.vu.nl

Universiteitsbibliotheek - Vrije Universiteit Amsterdam

Page Load Speed

3.3 sec in total

First Response

256 ms

Resources Loaded

2.4 sec

Page Rendered

654 ms

About Website

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

De UB is een inspirerende ontmoetingsplek, met alle informatie en kennis voor impact in wetenschap en maatschappij en al het materiaal om mee te leren.

Visit ub.vu.nl

Key Findings

We analyzed Ub.vu.nl page load time and found that the first response time was 256 ms and then it took 3.1 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

ub.vu.nl performance score

33

Measured Metrics

name

value

score

weighting

FCP (First Contentful Paint)

Value5.8 s

5/100

10%

LCP (Largest Contentful Paint)

Value22.6 s

0/100

25%

SI (Speed Index)

Value9.5 s

12/100

10%

TBT (Total Blocking Time)

Value490 ms

59/100

30%

CLS (Cumulative Layout Shift)

Value0.114

86/100

15%

TTI (Time to Interactive)

Value17.1 s

4/100

10%

Network Requests Diagram

ub.vu.nl

256 ms

universiteitsbibliotheek

684 ms

site.min.css

730 ms

VU-logo-nobg.svg

248 ms

5%20stappen%20VU%20reading%20list.jpg

804 ms

Our browser made a total of 26 requests to load all elements on the main page. We found that 4% of them (1 request) were addressed to the original Ub.vu.nl, 65% (17 requests) were made to Vu.nl and 31% (8 requests) were made to Assets.vu.nl. The less responsive or slowest element that took the longest time to load (1.2 sec) relates to the external source Vu.nl.

Page Optimization Overview & Recommendations

Page size can be reduced by 83.2 kB (8%)

Content Size

1.1 MB

After Optimization

995.1 kB

  • HTML
  • Images
  • JavaScript
  • CSS

In fact, the total size of Ub.vu.nl main page is 1.1 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. 55% of websites need less resources to load. Images take 979.6 kB which makes up the majority of the site volume.

HTML Optimization

-85%

Potential reduce by 83.0 kB

  • Original 98.2 kB
  • After minification 82.4 kB
  • After compression 15.2 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 15.7 kB, which is 16% 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 83.0 kB or 85% of the original size.

Image Optimization

-0%

Potential reduce by 0 B

  • Original 979.6 kB
  • After minification 979.6 kB

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. Ub Vu images are well optimized though.

JavaScript Optimization

-36%

Potential reduce by 156 B

  • Original 438 B
  • After minification 438 B
  • After compression 282 B

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 156 B or 36% of the original size.

CSS Optimization

-40%

Potential reduce by 59 B

  • Original 146 B
  • After minification 132 B
  • After compression 87 B

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. Ub.vu.nl needs all CSS files to be minified and compressed as it can save up to 59 B or 40% of the original size.

Requests Breakdown

We found no issues to fix!

Requests Now

14

After Optimization

14

  • Images
  • JavaScript
  • CSS

The browser has sent 14 CSS, Javascripts, AJAX and image requests in order to completely render the main page of Ub Vu. According to our analytics all requests are already optimized.

Network Requests Diagram

Accessibility Review

ub.vu.nl accessibility score

84

Accessibility Issues

ARIA

These are opportunities to improve the usage of ARIA in your application which may enhance the experience for users of assistive technology, like a screen reader.

Impact

Issue

High

[aria-*] attributes do not match their roles

High

[aria-hidden="true"] elements contain focusable descendents

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

Image elements do not have [alt] attributes

Best Practices

ub.vu.nl best practices score

92

Areas of Improvement

Trust and Safety

Impact

Issue

High

Does not use HTTPS

Low

Ensure CSP is effective against XSS attacks

General

Impact

Issue

Low

Detected JavaScript libraries

High

Missing source maps for large first-party JavaScript

SEO Factors

ub.vu.nl SEO score

83

Search Engine Optimization Advices

Crawling and Indexing

To appear in search results, crawlers need access to your app.

Impact

Issue

High

Links are not crawlable

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

    NL

  • Encoding

    UTF-8

Language claimed in HTML meta tag should match the language actually used on the web page. Otherwise Ub.vu.nl can be misinterpreted by Google and other search engines. Our service has detected that Dutch is used on the page, and it matches the claimed language. Our system also found out that Ub.vu.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 data is detected on the main page of Ub Vu. This is the best way to make the web page social media friendly. Here is how it looks like on Facebook: