Tools & Wizards About Us
zahlenzorro.de screenshot

Report Summary

  • 64

    Performance

    Renders faster than
    77% of other websites

  • 93

    Accessibility

    Visual factors better than
    that of 81% of websites

  • 83

    Best Practices

    More advanced features
    available than in
    55% of websites

  • 100

    SEO

    Google-friendlier than
    94% of websites

zahlenzorro.de

Mathe online üben - Klasse 1, 2, 3, 4 - ZAHLENZORRO

Page Load Speed

4.3 sec in total

First Response

359 ms

Resources Loaded

3.4 sec

Page Rendered

549 ms

zahlenzorro.de screenshot

About Website

Click here to check amazing ZAHLENZORRO content for Germany. Otherwise, check out these important facts you probably never knew about zahlenzorro.de

Online-Mathe-Aufgaben für die Grundschule: spannende Rechen-Geschichten ✓ Einmaleins-Training ✓ Knobelaufgaben ✓ VERA-Aufgaben ✓

Visit zahlenzorro.de

Key Findings

We analyzed Zahlenzorro.de page load time and found that the first response time was 359 ms and then it took 3.9 sec to load all DOM resources and completely render a web page. This is a poor result, as 65% of websites can load faster.

Performance Metrics

zahlenzorro.de performance score

64

Measured Metrics

name

value

score

weighting

FCP (First Contentful Paint)

Value2.4 s

69/100

10%

LCP (Largest Contentful Paint)

Value6.5 s

9/100

25%

SI (Speed Index)

Value3.8 s

83/100

10%

TBT (Total Blocking Time)

Value0 ms

100/100

30%

CLS (Cumulative Layout Shift)

Value0.21

59/100

15%

TTI (Time to Interactive)

Value4.8 s

79/100

10%

Network Requests Diagram

zahlenzorro.de

359 ms

zahlenzorro.westermann.de

572 ms

bootstrap.min.css

427 ms

fonts.css

319 ms

remixicon.css

438 ms

Our browser made a total of 36 requests to load all elements on the main page. We found that 3% of them (1 request) were addressed to the original Zahlenzorro.de, 92% (33 requests) were made to Zahlenzorro.westermann.de and 6% (2 requests) were made to Track.westermann.de. The less responsive or slowest element that took the longest time to load (1.9 sec) relates to the external source Zahlenzorro.westermann.de.

Page Optimization Overview & Recommendations

Page size can be reduced by 61.1 kB (7%)

Content Size

878.6 kB

After Optimization

817.5 kB

  • HTML
  • Images
  • JavaScript

In fact, the total size of Zahlenzorro.de main page is 878.6 kB. This result falls beyond the top 1M of websites and identifies a large and not optimized web page that may take ages to load. 30% of websites need less resources to load. Images take 767.6 kB which makes up the majority of the site volume.

HTML Optimization

-80%

Potential reduce by 31.9 kB

  • Original 39.9 kB
  • After minification 29.6 kB
  • After compression 8.0 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 10.3 kB, which is 26% 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 31.9 kB or 80% of the original size.

Image Optimization

-4%

Potential reduce by 27.0 kB

  • Original 767.6 kB
  • After minification 740.6 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. ZAHLENZORRO images are well optimized though.

JavaScript Optimization

-3%

Potential reduce by 2.2 kB

  • Original 71.1 kB
  • After minification 71.1 kB
  • After compression 68.9 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.

Requests Breakdown

Number of requests can be reduced by 7 (23%)

Requests Now

30

After Optimization

23

  • Images
  • JavaScript
  • CSS

The browser has sent 30 CSS, Javascripts, AJAX and image requests in order to completely render the main page of ZAHLENZORRO. We recommend that multiple CSS and JavaScript files should be merged into one by each type, as it can help reduce assets requests from 5 to 1 for JavaScripts and from 4 to 1 for CSS and as a result speed up the page load time.

Network Requests Diagram

zahlenzorro.de

zahlenzorro.de

359 ms

zahlenzorro.westermann.de

zahlenzorro.westermann.de

572 ms

bootstrap.min.css

bootstrap.min.css

427 ms

fonts.css

fonts.css

319 ms

remixicon.css

remixicon.css

438 ms

startpage.css

startpage.css

323 ms

jquery-3.4.1.min.js

jquery-3.4.1.min.js

465 ms

bootstrap.min.js

bootstrap.min.js

319 ms

bootstrap.tabcollapse.js

bootstrap.tabcollapse.js

631 ms

gds.js

gds.js

635 ms

piwik.js

piwik.js

644 ms

Kombi_grau.svg

Kombi_grau.svg

298 ms

zahlenzorro_maus.png

zahlenzorro_maus.png

279 ms

zahlenzorro_logo.png

zahlenzorro_logo.png

382 ms

Hero_Bild_links.jpg

Hero_Bild_links.jpg

523 ms

Hero_Bild_Mitte.jpg

Hero_Bild_Mitte.jpg

897 ms

Hero_Bild_rechts.jpg

Hero_Bild_rechts.jpg

695 ms

startseite_lizenzen.png

startseite_lizenzen.png

593 ms

startseite_demos.jpg

startseite_demos.jpg

818 ms

karo.svg

karo.svg

696 ms

startseite_geraete.png

startseite_geraete.png

837 ms

startseite_alfons.png

startseite_alfons.png

1010 ms

startseite_antolin.png

startseite_antolin.png

1009 ms

startseite_bibox.png

startseite_bibox.png

1010 ms

startseite_grundschuldiagnose.png

startseite_grundschuldiagnose.png

1132 ms

startseite_sammelbild.jpg

startseite_sammelbild.jpg

1357 ms

startseite_apps.jpg

startseite_apps.jpg

1417 ms

startseite_heft.jpg

startseite_heft.jpg

1427 ms

startseite_award_gigamaus2010.png

startseite_award_gigamaus2010.png

1322 ms

comenius_2010.png

comenius_2010.png

1327 ms

fragfinn.png

fragfinn.png

1445 ms

bsDruckschriftGru1-Regular.woff

bsDruckschriftGru1-Regular.woff

1701 ms

bsoperasans1-regular-webfont.woff

bsoperasans1-regular-webfont.woff

1909 ms

remixicon.woff

remixicon.woff

1940 ms

glyphicons-halflings-regular.woff

glyphicons-halflings-regular.woff

1790 ms

piwik.php

piwik.php

132 ms

Accessibility Review

zahlenzorro.de accessibility score

93

Accessibility Issues

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.

Tables and lists

These are opportunities to improve the experience of reading tabular or list data using assistive technology, like a screen reader.

Impact

Issue

High

Lists do not contain only <li> elements and script supporting elements (<script> and <template>).

Best Practices

zahlenzorro.de 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

SEO Factors

zahlenzorro.de SEO score

100

Search Engine Optimization Advices

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

    DE

  • Language Claimed

    DE

  • Encoding

    UTF-8

Language claimed in HTML meta tag should match the language actually used on the web page. Otherwise Zahlenzorro.de can be misinterpreted by Google and other search engines. Our service has detected that German is used on the page, and it matches the claimed language. Our system also found out that Zahlenzorro.de 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

zahlenzorro.de

Open Graph description is not detected on the main page of ZAHLENZORRO. 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: