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alter.cz screenshot

Report Summary

  • 57

    Performance

    Renders faster than
    73% of other websites

  • 90

    Accessibility

    Visual factors better than
    that of 74% of websites

  • 83

    Best Practices

    More advanced features
    available than in
    55% of websites

  • 90

    SEO

    Google-friendlier than
    68% of websites

alter.cz

| Alter e-shop

Page Load Speed

5.7 sec in total

First Response

1.2 sec

Resources Loaded

4.1 sec

Page Rendered

435 ms

alter.cz screenshot

About Website

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

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Visit alter.cz

Key Findings

We analyzed Alter.cz page load time and found that the first response time was 1.2 sec and then it took 4.5 sec to load all DOM resources and completely render a web page. This is a poor result, as 70% of websites can load faster.

Performance Metrics

alter.cz performance score

57

Measured Metrics

name

value

score

weighting

FCP (First Contentful Paint)

Value1.7 s

92/100

10%

LCP (Largest Contentful Paint)

Value10.6 s

0/100

25%

SI (Speed Index)

Value8.2 s

20/100

10%

TBT (Total Blocking Time)

Value120 ms

97/100

30%

CLS (Cumulative Layout Shift)

Value0.002

100/100

15%

TTI (Time to Interactive)

Value11.8 s

17/100

10%

Network Requests Diagram

alter.cz

1170 ms

alter.cz

1049 ms

css_-XkYsqNOfa5tqZFsRdaCsb7Ahp8DKMZlrJmCN0ABhWo.css

96 ms

css_ZIPigOHAbpl9VHHKKlsIrvDoolqjjWAckzpqMYQKpfY.css

373 ms

js_laO8sUOhNalghi8DLtblg6mdmdjNC5hSk7zZDI0z8Qk.js

568 ms

Our browser made a total of 58 requests to load all elements on the main page. We found that all of those requests were addressed to Alter.cz and no external sources were called. The less responsive or slowest element that took the longest time to load (1.2 sec) belongs to the original domain Alter.cz.

Page Optimization Overview & Recommendations

Page size can be reduced by 839.7 kB (9%)

Content Size

8.9 MB

After Optimization

8.1 MB

  • HTML
  • Images
  • JavaScript
  • CSS

In fact, the total size of Alter.cz main page is 8.9 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 8.7 MB which makes up the majority of the site volume.

HTML Optimization

-82%

Potential reduce by 56.3 kB

  • Original 68.9 kB
  • After minification 58.6 kB
  • After compression 12.5 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 10.2 kB, which is 15% 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 56.3 kB or 82% of the original size.

Image Optimization

-9%

Potential reduce by 783.2 kB

  • Original 8.7 MB
  • After minification 7.9 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. Alter images are well optimized though.

JavaScript Optimization

-0%

Potential reduce by 34 B

  • Original 127.0 kB
  • After minification 127.0 kB
  • After compression 127.0 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

-1%

Potential reduce by 111 B

  • Original 9.3 kB
  • After minification 9.3 kB
  • After compression 9.2 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. Alter.cz has all CSS files already compressed.

Requests Breakdown

Number of requests can be reduced by 3 (7%)

Requests Now

46

After Optimization

43

  • Images
  • JavaScript
  • CSS

The browser has sent 46 CSS, Javascripts, AJAX and image requests in order to completely render the main page of Alter. 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 JavaScripts and as a result speed up the page load time.

Network Requests Diagram

alter.cz

alter.cz

1170 ms

alter.cz

alter.cz

1049 ms

css_-XkYsqNOfa5tqZFsRdaCsb7Ahp8DKMZlrJmCN0ABhWo.css

css_-XkYsqNOfa5tqZFsRdaCsb7Ahp8DKMZlrJmCN0ABhWo.css

96 ms

css_ZIPigOHAbpl9VHHKKlsIrvDoolqjjWAckzpqMYQKpfY.css

css_ZIPigOHAbpl9VHHKKlsIrvDoolqjjWAckzpqMYQKpfY.css

373 ms

js_laO8sUOhNalghi8DLtblg6mdmdjNC5hSk7zZDI0z8Qk.js

js_laO8sUOhNalghi8DLtblg6mdmdjNC5hSk7zZDI0z8Qk.js

568 ms

eu_cookie_compliance.min.js

eu_cookie_compliance.min.js

286 ms

accordion.frontend.min.js

accordion.frontend.min.js

285 ms

js_b9YZ1_QNNOlAYn7HANJL_eWiWuW2QG3nyu5F0fcBicM.js

js_b9YZ1_QNNOlAYn7HANJL_eWiWuW2QG3nyu5F0fcBicM.js

607 ms

multilicence_zdarma_clanek_new.jpg

multilicence_zdarma_clanek_new.jpg

565 ms

%C4%8DtverecCJ3.png

%C4%8DtverecCJ3.png

660 ms

Z-s-klickou_clanek2.JPG

Z-s-klickou_clanek2.JPG

567 ms

092157%20Zeme%20ve%20vesmiru.jpg

092157%20Zeme%20ve%20vesmiru.jpg

652 ms

Technika%201.png

Technika%201.png

941 ms

092152%20PS%20MATEMATIKA%201_4%20SVP_obalka_2020.jpg

092152%20PS%20MATEMATIKA%201_4%20SVP_obalka_2020.jpg

574 ms

ProductType1.svg

ProductType1.svg

656 ms

ProductType3.svg

ProductType3.svg

662 ms

092819_Pisanka_III_Z_s_klickou_OBALKA.jpg

092819_Pisanka_III_Z_s_klickou_OBALKA.jpg

702 ms

092951_Pisanka_ke_Slabikari_3_Z_obalka_s_Z_2024.jpg

092951_Pisanka_ke_Slabikari_3_Z_obalka_s_Z_2024.jpg

748 ms

092146_Slabikar_1_dil_obalka_2017.jpg

092146_Slabikar_1_dil_obalka_2017.jpg

750 ms

logo-alter-footer.png

logo-alter-footer.png

754 ms

logo_facebook.png

logo_facebook.png

757 ms

icon-user-osoba.png

icon-user-osoba.png

384 ms

icon-user-skola.png

icon-user-skola.png

428 ms

icon-login-lock.png

icon-login-lock.png

431 ms

icon-login-registration.png

icon-login-registration.png

436 ms

shop-cart.png

shop-cart.png

438 ms

e_letter_white.svg

e_letter_white.svg

478 ms

icon_search.png

icon_search.png

523 ms

SliderZZZZZZz.jpg

SliderZZZZZZz.jpg

902 ms

SliderCJ3-b2.jpg

SliderCJ3-b2.jpg

719 ms

ZivaAbecedaSlider6.jpg

ZivaAbecedaSlider6.jpg

1013 ms

PL-Nase-vlast-2_0.jpg

PL-Nase-vlast-2_0.jpg

856 ms

PL-Zeme-ve-vesmiru-OK.jpg

PL-Zeme-ve-vesmiru-OK.jpg

714 ms

Zem%C4%9B%20ve%20vesm%C3%ADru.jpg

Zem%C4%9B%20ve%20vesm%C3%ADru.jpg

628 ms

Na%C5%A1e%20vlast%20ALTER_1.jpg

Na%C5%A1e%20vlast%20ALTER_1.jpg

728 ms

Ucebnice%20novejsi%20dejiny.jpg

Ucebnice%20novejsi%20dejiny.jpg

818 ms

PL%20novejsi%20dejiny_0.jpg

PL%20novejsi%20dejiny_0.jpg

820 ms

PL%20starsi%20dejiny_0.jpg

PL%20starsi%20dejiny_0.jpg

827 ms

Dejiny.jpg

Dejiny.jpg

919 ms

Pisanky_3.jpg

Pisanky_3.jpg

920 ms

clovek_a_technika_slide_0.jpg

clovek_a_technika_slide_0.jpg

924 ms

PL-clovek-a-technika-slide-OK.jpg

PL-clovek-a-technika-slide-OK.jpg

808 ms

right-arrow-icon-white.png

right-arrow-icon-white.png

844 ms

footer-people-big.png

footer-people-big.png

857 ms

montserrat-v14-latin-ext_latin-regular.woff

montserrat-v14-latin-ext_latin-regular.woff

859 ms

montserrat-v14-latin-ext_latin-500.woff

montserrat-v14-latin-ext_latin-500.woff

865 ms

montserrat-v14-latin-ext_latin-300.woff

montserrat-v14-latin-ext_latin-300.woff

871 ms

montserrat-v14-latin-ext_latin-600.woff

montserrat-v14-latin-ext_latin-600.woff

854 ms

montserrat-v14-latin-ext_latin-700.woff

montserrat-v14-latin-ext_latin-700.woff

878 ms

montserrat-v14-latin-ext_latin-800.woff

montserrat-v14-latin-ext_latin-800.woff

876 ms

montserrat-v14-latin-ext_latin-900.woff

montserrat-v14-latin-ext_latin-900.woff

874 ms

fa-solid-900.woff

fa-solid-900.woff

835 ms

fa-regular-400.woff

fa-regular-400.woff

828 ms

fa-regular-400.woff

fa-regular-400.woff

1126 ms

footer-address-icon.png

footer-address-icon.png

863 ms

footer-phone-icon.png

footer-phone-icon.png

861 ms

footer-numbers-icon.png

footer-numbers-icon.png

825 ms

footer-mail-icon.png

footer-mail-icon.png

783 ms

Accessibility Review

alter.cz accessibility score

90

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.

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

Links do not have a discernible name

Best Practices

alter.cz 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

SEO Factors

alter.cz SEO score

90

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

High

Tap targets are not sized appropriately

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 Alter.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 Alter.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

alter.cz

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