4.6 sec in total
758 ms
3.7 sec
145 ms
Welcome to zvdd.de homepage info - get ready to check Zvdd best content for Switzerland right away, or after learning these important things about zvdd.de
ZVDD ist das Nachweisportal für in Deutschland erstellte Digitalisate von Druckwerken vom 15. Jahrhundert bis heute.
Visit zvdd.deWe analyzed Zvdd.de page load time and found that the first response time was 758 ms and then it took 3.8 sec to load all DOM resources and completely render a web page. This is a poor result, as 65% of websites can load faster.
zvdd.de performance score
name
value
score
weighting
Value3.6 s
32/100
10%
Value5.5 s
19/100
25%
Value5.8 s
50/100
10%
Value20 ms
100/100
30%
Value0.137
79/100
15%
Value4.0 s
88/100
10%
758 ms
99 ms
495 ms
299 ms
299 ms
Our browser made a total of 25 requests to load all elements on the main page. We found that 92% of them (23 requests) were addressed to the original Zvdd.de, 8% (2 requests) were made to Piwik.gwdg.de. The less responsive or slowest element that took the longest time to load (1 sec) belongs to the original domain Zvdd.de.
Page size can be reduced by 149.4 kB (45%)
334.0 kB
184.6 kB
In fact, the total size of Zvdd.de main page is 334.0 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. 15% of websites need less resources to load. Javascripts take 182.0 kB which makes up the majority of the site volume.
Potential reduce by 16.7 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. HTML code on this page is well minified. It is highly recommended that content of this web page should be compressed using GZIP, as it can save up to 16.7 kB or 71% of the original size.
Potential reduce by 1.4 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. Zvdd images are well optimized though.
Potential reduce by 114.2 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 114.2 kB or 63% of the original size.
Potential reduce by 17.2 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. Zvdd.de needs all CSS files to be minified and compressed as it can save up to 17.2 kB or 81% of the original size.
Number of requests can be reduced by 3 (14%)
21
18
The browser has sent 21 CSS, Javascripts, AJAX and image requests in order to completely render the main page of Zvdd. We recommend that multiple CSS and JavaScript files should be merged into one by each type, as it can help reduce assets requests from 4 to 1 for CSS and as a result speed up the page load time.
758 ms
stylesheet_73a41d518f.css
99 ms
jquery-1.9.x-1.9.x.js
495 ms
screen_color.css
299 ms
screen.css
299 ms
xajax.js
406 ms
piwik.js
685 ms
zvdd_logo.gif
99 ms
zvdd_title.gif
103 ms
search.png
103 ms
digital_analog_01.jpg
294 ms
csm_indicator_36839e39fd.png
100 ms
rss.png
198 ms
sdd-logo-edit2b-web_neu.png
197 ms
logo_sub.png
204 ms
logo_dfg.gif
213 ms
872 ms
891 ms
1034 ms
piwik.php
145 ms
clear.gif
103 ms
PPN1895665698.jpg
104 ms
PPN1895664322.jpg
99 ms
PPN1895989272.jpg
99 ms
print.css
100 ms
zvdd.de accessibility score
Contrast
These are opportunities to improve the legibility of your content.
Impact
Issue
Background and foreground colors do not have a sufficient contrast ratio.
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
Image elements do not have [alt] attributes
<input type="image"> elements do not have [alt] text
Form elements do not have associated labels
Links do not have a discernible name
zvdd.de best practices score
Trust and Safety
Impact
Issue
Does not use HTTPS
Includes front-end JavaScript libraries with known security vulnerabilities
Ensure CSP is effective against XSS attacks
User Experience
Impact
Issue
Serves images with low resolution
General
Impact
Issue
Detected JavaScript libraries
zvdd.de SEO score
Crawling and Indexing
To appear in search results, crawlers need access to your app.
Impact
Issue
robots.txt is not valid
Content Best Practices
Format your HTML in a way that enables crawlers to better understand your app’s content.
Impact
Issue
Image elements do not have [alt] attributes
DE
DE
UTF-8
Language claimed in HTML meta tag should match the language actually used on the web page. Otherwise Zvdd.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 Zvdd.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.
zvdd.de
Open Graph description is not detected on the main page of Zvdd. 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: