Tools & Wizards About Us
web.o2.cz screenshot

Report Summary

  • 20

    Performance

    Renders faster than
    37% of other websites

  • 90

    Accessibility

    Visual factors better than
    that of 74% of websites

  • 75

    Best Practices

    More advanced features
    available than in
    35% of websites

  • 93

    SEO

    Google-friendlier than
    83% of websites

web.o2.cz

O2 | Volání, internet, televize a balíčky O2 Spolu

Page Load Speed

11.9 sec in total

First Response

393 ms

Resources Loaded

9.6 sec

Page Rendered

1.9 sec

web.o2.cz screenshot

About Website

Welcome to web.o2.cz homepage info - get ready to check Web O2 best content for Czech Republic right away, or after learning these important things about web.o2.cz

O2 nabízí výhodné volání, široké pokrytí i rychlost internetu a další telekomunikační služby. Jejich kombinací i nákupem on-line ušetříte, spojte si služby v O2 Spolu. Zařiďte vše v aplikaci Moje O2.

Visit web.o2.cz

Key Findings

We analyzed Web.o2.cz page load time and found that the first response time was 393 ms and then it took 11.5 sec to load all DOM resources and completely render a web page. This is a poor result, as 90% of websites can load faster.

Performance Metrics

web.o2.cz performance score

20

Measured Metrics

name

value

score

weighting

FCP (First Contentful Paint)

Value4.6 s

13/100

10%

LCP (Largest Contentful Paint)

Value13.2 s

0/100

25%

SI (Speed Index)

Value10.2 s

8/100

10%

TBT (Total Blocking Time)

Value1,850 ms

9/100

30%

CLS (Cumulative Layout Shift)

Value0.004

100/100

15%

TTI (Time to Interactive)

Value21.7 s

1/100

10%

Network Requests Diagram

web.o2.cz

393 ms

www.o2.cz

395 ms

osobni

812 ms

index.scss

865 ms

-a220821

294 ms

Our browser made a total of 120 requests to load all elements on the main page. We found that 1% of them (1 request) were addressed to the original Web.o2.cz, 83% (100 requests) were made to O2.cz and 5% (6 requests) were made to S.o2.cz. The less responsive or slowest element that took the longest time to load (3.3 sec) relates to the external source O2.cz.

Page Optimization Overview & Recommendations

Page size can be reduced by 658.8 kB (42%)

Content Size

1.6 MB

After Optimization

920.6 kB

  • HTML
  • Images
  • JavaScript
  • CSS

In fact, the total size of Web.o2.cz main page is 1.6 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. 50% of websites need less resources to load. Images take 791.2 kB which makes up the majority of the site volume.

HTML Optimization

-79%

Potential reduce by 204.7 kB

  • Original 259.4 kB
  • After minification 250.6 kB
  • After compression 54.7 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 204.7 kB or 79% of the original size.

Image Optimization

-33%

Potential reduce by 257.2 kB

  • Original 791.2 kB
  • After minification 534.0 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. Obviously, Web O2 needs image optimization as it can save up to 257.2 kB or 33% of the original volume. The most popular and efficient tools for JPEG and PNG image optimization are Jpegoptim and PNG Crush.

JavaScript Optimization

-44%

Potential reduce by 196.3 kB

  • Original 450.1 kB
  • After minification 449.8 kB
  • After compression 253.8 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 196.3 kB or 44% of the original size.

CSS Optimization

-1%

Potential reduce by 602 B

  • Original 78.7 kB
  • After minification 78.7 kB
  • After compression 78.1 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. Web.o2.cz has all CSS files already compressed.

Requests Breakdown

Number of requests can be reduced by 18 (17%)

Requests Now

107

After Optimization

89

  • AJAX
  • Images
  • JavaScript
  • CSS

The browser has sent 107 CSS, Javascripts, AJAX and image requests in order to completely render the main page of Web O2. We recommend that multiple CSS and JavaScript files should be merged into one by each type, as it can help reduce assets requests from 19 to 1 for JavaScripts and as a result speed up the page load time.

Network Requests Diagram

web.o2.cz

web.o2.cz

393 ms

www.o2.cz

www.o2.cz

395 ms

osobni

osobni

812 ms

index.scss

index.scss

865 ms

-a220821

-a220821

294 ms

index.js

index.js

60 ms

launch-EN01534af7e30646e8b078ac64dc75500b.min.js

launch-EN01534af7e30646e8b078ac64dc75500b.min.js

18 ms

-a74517

-a74517

575 ms

-a74537.js

-a74537.js

911 ms

cmp.php

cmp.php

666 ms

cmp_final.min.js

cmp_final.min.js

971 ms

exponea.min.js

exponea.min.js

550 ms

AppMeasurement.min.js

AppMeasurement.min.js

24 ms

AppMeasurement_Module_ActivityMap.min.js

AppMeasurement_Module_ActivityMap.min.js

25 ms

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764 ms

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668 ms

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575 ms

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766 ms

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858 ms

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1735 ms

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1738 ms

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1923 ms

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2009 ms

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2023 ms

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2022 ms

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2024 ms

-a212871

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2026 ms

-a212911

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2213 ms

-a212383

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2299 ms

gtm.js

gtm.js

143 ms

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2302 ms

actions.js

actions.js

540 ms

persoo.js

persoo.js

629 ms

persoo-ui.js

persoo-ui.js

625 ms

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2324 ms

s51082211176399

s51082211176399

6 ms

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2091 ms

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2035 ms

ncas-init.js

ncas-init.js

1929 ms

bV8xLndfMzQ1MjAucl9HRFBSLmxfY3Mudi5wLnRfMTY3ODgueHRfMjUy.js

bV8xLndfMzQ1MjAucl9HRFBSLmxfY3Mudi5wLnRfMTY3ODgueHRfMjUy.js

379 ms

workflow.js

workflow.js

111 ms

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2018 ms

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2085 ms

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2227 ms

persooAutocomplete.js

persooAutocomplete.js

86 ms

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2195 ms

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2141 ms

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2143 ms

OnAir-Bold.woff

OnAir-Bold.woff

2209 ms

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2002 ms

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2128 ms

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2316 ms

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2141 ms

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2615 ms

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2013 ms

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2131 ms

box-bg.jpg

box-bg.jpg

2235 ms

box-1-object-mobile.png

box-1-object-mobile.png

2566 ms

box-2-object-mobile.png

box-2-object-mobile.png

2655 ms

122 ms

203 ms

box-3-object-mobile.png

box-3-object-mobile.png

2504 ms

box-4-bg.jpg

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2232 ms

box-4-object-mobile.png

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2519 ms

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2426 ms

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2743 ms

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2705 ms

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3269 ms

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2840 ms

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2429 ms

osobni

osobni

2415 ms

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667 ms

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479 ms

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386 ms

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573 ms

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294 ms

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476 ms

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583 ms

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677 ms

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765 ms

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768 ms

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864 ms

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873 ms

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957 ms

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966 ms

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1055 ms

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1156 ms

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1162 ms

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1247 ms

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1256 ms

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1345 ms

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1349 ms

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1449 ms

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1536 ms

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1545 ms

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1635 ms

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1731 ms

workflow.js

workflow.js

92 ms

RC304d1437ce8b4a6abf22884e95aaa7c6-source.min.js

RC304d1437ce8b4a6abf22884e95aaa7c6-source.min.js

3 ms

Accessibility Review

web.o2.cz accessibility score

90

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

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.

Best Practices

web.o2.cz best practices score

75

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

Browser errors were logged to the console

High

Missing source maps for large first-party JavaScript

SEO Factors

web.o2.cz SEO score

93

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

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

    CS

  • Language Claimed

    CS

  • Encoding

    UTF-8

Language claimed in HTML meta tag should match the language actually used on the web page. Otherwise Web.o2.cz can be misinterpreted by Google and other search engines. Our service has detected that Czech is used on the page, and it matches the claimed language. Our system also found out that Web.o2.cz 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

web.o2.cz

Open Graph data is detected on the main page of Web O2. This is the best way to make the web page social media friendly. Here is how it looks like on Facebook: