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erasmusmc.nl screenshot

Report Summary

  • 26

    Performance

    Renders faster than
    45% of other websites

  • 86

    Accessibility

    Visual factors better than
    that of 61% of websites

  • 83

    Best Practices

    More advanced features
    available than in
    55% of websites

  • 86

    SEO

    Google-friendlier than
    60% of websites

erasmusmc.nl

Erasmus MC: Patiëntenzorg

Page Load Speed

7.2 sec in total

First Response

269 ms

Resources Loaded

5.7 sec

Page Rendered

1.2 sec

erasmusmc.nl screenshot

About Website

Click here to check amazing Erasmus MC content for Netherlands. Otherwise, check out these important facts you probably never knew about erasmusmc.nl

Welkom bij het Erasmus MC in Rotterdam. Wij staan voor een gezonde bevolking en excellente zorg door wetenschappelijk onderzoek en onderwijs.

Visit erasmusmc.nl

Key Findings

We analyzed Erasmusmc.nl page load time and found that the first response time was 269 ms and then it took 6.9 sec to load all DOM resources and completely render a web page. This is a poor result, as 80% of websites can load faster.

Performance Metrics

erasmusmc.nl performance score

26

Measured Metrics

name

value

score

weighting

FCP (First Contentful Paint)

Value4.6 s

13/100

10%

LCP (Largest Contentful Paint)

Value5.7 s

16/100

25%

SI (Speed Index)

Value9.3 s

13/100

10%

TBT (Total Blocking Time)

Value1,290 ms

18/100

30%

CLS (Cumulative Layout Shift)

Value0.097

90/100

15%

TTI (Time to Interactive)

Value16.8 s

5/100

10%

Network Requests Diagram

erasmusmc.nl

269 ms

www.erasmusmc.nl

472 ms

1230 ms

container_GOFaCYDR.js

899 ms

main.css

682 ms

Our browser made a total of 74 requests to load all elements on the main page. We found that 74% of them (55 requests) were addressed to the original Erasmusmc.nl, 8% (6 requests) were made to Youtube-nocookie.com and 8% (6 requests) were made to Erasmusmc-amazingerasmusmc.s3.eu-central-1.amazonaws.com. The less responsive or slowest element that took the longest time to load (2.3 sec) belongs to the original domain Erasmusmc.nl.

Page Optimization Overview & Recommendations

Page size can be reduced by 342.8 kB (14%)

Content Size

2.5 MB

After Optimization

2.2 MB

  • HTML
  • Images
  • JavaScript
  • CSS

In fact, the total size of Erasmusmc.nl main page is 2.5 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. 80% of websites need less resources to load and that’s why Accessify’s recommendations for optimization and resource minification can be helpful for this project. Images take 1.8 MB which makes up the majority of the site volume.

HTML Optimization

-91%

Potential reduce by 173.3 kB

  • Original 190.3 kB
  • After minification 149.5 kB
  • After compression 17.0 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 40.8 kB, which is 21% 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 173.3 kB or 91% of the original size.

Image Optimization

-9%

Potential reduce by 166.6 kB

  • Original 1.8 MB
  • After minification 1.6 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. Erasmus MC images are well optimized though.

JavaScript Optimization

-1%

Potential reduce by 2.7 kB

  • Original 442.8 kB
  • After minification 442.8 kB
  • After compression 440.1 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. This website has mostly compressed JavaScripts.

CSS Optimization

-0%

Potential reduce by 257 B

  • Original 97.0 kB
  • After minification 97.0 kB
  • After compression 96.7 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. Erasmusmc.nl has all CSS files already compressed.

Requests Breakdown

Number of requests can be reduced by 25 (38%)

Requests Now

65

After Optimization

40

  • AJAX
  • Images
  • JavaScript
  • CSS

The browser has sent 65 CSS, Javascripts, AJAX and image requests in order to completely render the main page of Erasmus MC. We recommend that multiple CSS and JavaScript files should be merged into one by each type, as it can help reduce assets requests from 6 to 1 for JavaScripts and as a result speed up the page load time.

Network Requests Diagram

erasmusmc.nl

erasmusmc.nl

269 ms

www.erasmusmc.nl

www.erasmusmc.nl

472 ms

1230 ms

container_GOFaCYDR.js

container_GOFaCYDR.js

899 ms

main.css

main.css

682 ms

full-colour-svg-main-brand-responsive-1-4.svg

full-colour-svg-main-brand-responsive-1-4.svg

761 ms

L29R6IA7i5U

L29R6IA7i5U

133 ms

Dalinghaus-Lange-320x240.jpg

Dalinghaus-Lange-320x240.jpg

738 ms

main.js

main.js

685 ms

grant-young-investigator-320x240.jpg

grant-young-investigator-320x240.jpg

734 ms

Foto-Gert-Jan-Kleinrensink-bewerkt-2-minder-kleur-320x240.jpg

Foto-Gert-Jan-Kleinrensink-bewerkt-2-minder-kleur-320x240.jpg

809 ms

high_marionkoopmans0420-007-320x240.jpg

high_marionkoopmans0420-007-320x240.jpg

809 ms

DNA-streng2-1-scaled-1-320x240.jpg

DNA-streng2-1-scaled-1-320x240.jpg

808 ms

amazing_Bindels-Patrick-320x240.jpg

amazing_Bindels-Patrick-320x240.jpg

809 ms

hp_carrousel-daktuin.jpg

hp_carrousel-daktuin.jpg

1111 ms

hp_carrousel-research.jpg

hp_carrousel-research.jpg

1148 ms

hp_carrousel-onderwijs.jpg

hp_carrousel-onderwijs.jpg

1064 ms

appointment-fills.svg

appointment-fills.svg

1061 ms

visiting-hours-fills.svg

visiting-hours-fills.svg

1059 ms

contact-and-route-fills.svg

contact-and-route-fills.svg

1189 ms

receipe-fills.svg

receipe-fills.svg

1641 ms

policlinic-fills.svg

policlinic-fills.svg

1642 ms

erasmus-mc-iconen-mijn-dossier.svg

erasmus-mc-iconen-mijn-dossier.svg

1457 ms

jason6.jpg

jason6.jpg

1283 ms

bezoekers-plein-zoeken-bewegwijzering.jpg

bezoekers-plein-zoeken-bewegwijzering.jpg

1729 ms

202001_zuidplein_558a2946_irisvandenbroek.jpg

202001_zuidplein_558a2946_irisvandenbroek.jpg

1636 ms

vaccinatie-kind.jpg

vaccinatie-kind.jpg

1562 ms

westzeedijk-garage.jpg

westzeedijk-garage.jpg

1920 ms

foto-artikel-mantelzorg.jpg

foto-artikel-mantelzorg.jpg

1983 ms

patientpanel-5.jpeg

patientpanel-5.jpeg

1942 ms

shutterstock_719469181.jpg

shutterstock_719469181.jpg

2013 ms

hartjerotterdam-hartjeklein.png

hartjerotterdam-hartjeklein.png

2118 ms

back-to-top-button.svg

back-to-top-button.svg

1817 ms

icon-facebook.svg

icon-facebook.svg

1937 ms

icon-instagram.svg

icon-instagram.svg

2009 ms

icon-twitter.svg

icon-twitter.svg

2027 ms

icon-linkedin.svg

icon-linkedin.svg

2030 ms

icon-youtube.svg

icon-youtube.svg

2078 ms

icon-256x256.png

icon-256x256.png

2283 ms

logo-footer.svg

logo-footer.svg

2100 ms

www-player.css

www-player.css

6 ms

www-embed-player.js

www-embed-player.js

38 ms

base.js

base.js

79 ms

jRYISRuM9q7e_xyYaLp_fsq3qnLjbNevd8JDa-bOkpI.js

jRYISRuM9q7e_xyYaLp_fsq3qnLjbNevd8JDa-bOkpI.js

319 ms

embed.js

embed.js

129 ms

KFOmCnqEu92Fr1Mu4mxP.ttf

KFOmCnqEu92Fr1Mu4mxP.ttf

141 ms

KFOlCnqEu92Fr1MmEU9fBBc9.ttf

KFOlCnqEu92Fr1MmEU9fBBc9.ttf

212 ms

emergency.svg

emergency.svg

1600 ms

icon-chevron-down.png

icon-chevron-down.png

1661 ms

icon-chevron-right-bold.svg

icon-chevron-right-bold.svg

1659 ms

dark_mode.svg

dark_mode.svg

1673 ms

translucent_squares_bg_overlay_green.svg

translucent_squares_bg_overlay_green.svg

1662 ms

chevron_right_filled.svg

chevron_right_filled.svg

2109 ms

background-climbing-pattern-right-to-left.svg

background-climbing-pattern-right-to-left.svg

2212 ms

icon-boxed-external-link-white.svg

icon-boxed-external-link-white.svg

1804 ms

chevron-right-filled-blue.svg

chevron-right-filled-blue.svg

1773 ms

Arrow-right-green.svg

Arrow-right-green.svg

2092 ms

Create

Create

135 ms

piwik.php

piwik.php

228 ms

montserrat-regular.woff

montserrat-regular.woff

1724 ms

montserrat-medium.woff

montserrat-medium.woff

1849 ms

montserrat-semibold.woff

montserrat-semibold.woff

1845 ms

GenerateIT

GenerateIT

19 ms

montserrat-bold.woff

montserrat-bold.woff

2206 ms

icon-boxed-external-link-green.svg

icon-boxed-external-link-green.svg

2167 ms

Arrow-right-button-green.svg

Arrow-right-button-green.svg

2127 ms

chevron-right-filled-green.svg

chevron-right-filled-green.svg

1851 ms

header_contact-poliklinieken.jpg

header_contact-poliklinieken.jpg

1840 ms

nfu-banner-basketbal.png

nfu-banner-basketbal.png

2206 ms

icon-chevron-right--white.svg

icon-chevron-right--white.svg

1689 ms

icon-phone.svg

icon-phone.svg

1753 ms

logo-pattern-end.svg

logo-pattern-end.svg

1765 ms

logo-pattern.svg

logo-pattern.svg

1674 ms

log_event

log_event

15 ms

Accessibility Review

erasmusmc.nl accessibility score

86

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 IDs are not unique

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

erasmusmc.nl best practices score

83

Areas of Improvement

Trust and Safety

Impact

Issue

High

Does not use HTTPS

Low

Ensure CSP is effective against XSS attacks

User Experience

Impact

Issue

High

Displays images with incorrect aspect ratio

General

Impact

Issue

Low

Detected JavaScript libraries

High

Missing source maps for large first-party JavaScript

SEO Factors

erasmusmc.nl SEO score

86

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

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 Erasmusmc.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 Erasmusmc.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

erasmusmc.nl

Open Graph data is detected on the main page of Erasmus MC. This is the best way to make the web page social media friendly. Here is how it looks like on Facebook: