Report Summary

  • 26

    Performance

    Renders faster than
    45% of other websites

  • 73

    Accessibility

    Visual factors better than
    that of 38% of websites

  • 58

    Best Practices

    More advanced features
    available than in
    20% of websites

  • 83

    SEO

    Google-friendlier than
    46% of websites

co2levels.org

CO2 Levels: Current & Historic Atmospheric Carbon Dioxide / Global Temperature Graph & Widget

Page Load Speed

3.1 sec in total

First Response

23 ms

Resources Loaded

2.7 sec

Page Rendered

344 ms

co2levels.org screenshot

About Website

Click here to check amazing CO2 Levels content. Otherwise, check out these important facts you probably never knew about co2levels.org

See how CO2 levels have never been higher with this fully interactive Atmospheric Carbon Dioxide (CO2) graph featuring current & historical CO2 levels and global temperatures. A project by the 2 Degre...

Visit co2levels.org

Key Findings

We analyzed Co2levels.org page load time and found that the first response time was 23 ms and then it took 3 sec to load all DOM resources and completely render a web page. This is a poor result, as 55% of websites can load faster.

Performance Metrics

co2levels.org performance score

26

Measured Metrics

name

value

score

weighting

FCP (First Contentful Paint)

Value2.2 s

79/100

10%

LCP (Largest Contentful Paint)

Value19.1 s

0/100

25%

SI (Speed Index)

Value14.8 s

1/100

10%

TBT (Total Blocking Time)

Value1,750 ms

10/100

30%

CLS (Cumulative Layout Shift)

Value0

100/100

15%

TTI (Time to Interactive)

Value19.6 s

2/100

10%

Network Requests Diagram

co2levels.org

23 ms

co2levels.org

330 ms

purecookie.css%20XXX

88 ms

purecookie.js%20XXXX

251 ms

bootstrap.min.css

256 ms

Our browser made a total of 83 requests to load all elements on the main page. We found that 45% of them (37 requests) were addressed to the original Co2levels.org, 14% (12 requests) were made to Climatelevels.org and 8% (7 requests) were made to Fonts.gstatic.com. The less responsive or slowest element that took the longest time to load (799 ms) belongs to the original domain Co2levels.org.

Page Optimization Overview & Recommendations

Page size can be reduced by 932.8 kB (40%)

Content Size

2.3 MB

After Optimization

1.4 MB

In fact, the total size of Co2levels.org main page is 2.3 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. Only a small number of websites need less resources to load. Javascripts take 879.8 kB which makes up the majority of the site volume.

HTML Optimization

-69%

Potential reduce by 582.3 kB

  • Original 839.0 kB
  • After minification 832.6 kB
  • After compression 256.7 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 582.3 kB or 69% of the original size.

Image Optimization

-13%

Potential reduce by 64.8 kB

  • Original 483.7 kB
  • After minification 418.9 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, CO2 Levels needs image optimization as it can save up to 64.8 kB or 13% of the original volume. The most popular and efficient tools for JPEG and PNG image optimization are Jpegoptim and PNG Crush.

JavaScript Optimization

-31%

Potential reduce by 271.0 kB

  • Original 879.8 kB
  • After minification 879.8 kB
  • After compression 608.8 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 271.0 kB or 31% of the original size.

CSS Optimization

-13%

Potential reduce by 14.8 kB

  • Original 113.0 kB
  • After minification 113.0 kB
  • After compression 98.2 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. Co2levels.org needs all CSS files to be minified and compressed as it can save up to 14.8 kB or 13% of the original size.

Requests Breakdown

Number of requests can be reduced by 45 (63%)

Requests Now

71

After Optimization

26

The browser has sent 71 CSS, Javascripts, AJAX and image requests in order to completely render the main page of CO2 Levels. We recommend that multiple CSS and JavaScript files should be merged into one by each type, as it can help reduce assets requests from 33 to 1 for JavaScripts and from 14 to 1 for CSS and as a result speed up the page load time.

Accessibility Review

co2levels.org accessibility score

73

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.

Navigation

These are opportunities to improve keyboard navigation in your application.

Impact

Issue

High

Heading elements are not in a sequentially-descending order

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

High

Links do not have a discernible name

Best practices

These items highlight common accessibility best practices.

Impact

Issue

High

[user-scalable="no"] is used in the <meta name="viewport"> element or the [maximum-scale] attribute is less than 5.

Best Practices

co2levels.org best practices score

58

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

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

Page has valid source maps

High

Issues were logged in the Issues panel in Chrome Devtools

SEO Factors

co2levels.org SEO score

83

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

    EN

  • Language Claimed

    EN

  • Encoding

    UTF-8

Language claimed in HTML meta tag should match the language actually used on the web page. Otherwise Co2levels.org can be misinterpreted by Google and other search engines. Our service has detected that English is used on the page, and it matches the claimed language. Our system also found out that Co2levels.org 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

Open Graph data is detected on the main page of CO2 Levels. This is the best way to make the web page social media friendly. Here is how it looks like on Facebook: