Page summary

Summary

Metric	Value
Page metrics
Performance Score	94
Total Page Transfer Size	94.9 KB
Requests	7
Timing metrics
TTFB [median]	435 ms
First Paint [median]	2.300 s
Fully Loaded [median]	3.173 s
Google Web Vitals
TTFB [median]	435 ms
First Contentful Paint (FCP) [median]	2.300 s
Largest Contentful Paint (LCP) [median]	2.300 s
Cumulative Layout Shift (CLS) [median]	0.00
Interaction To Next Paint (INP) [median]	1.812 s
Total Blocking Time [median]	484 ms
Max Potential FID [median]	534 ms
CPU metrics
CPU long tasks [median]	3
CPU longest task duration	1.568 s
CPU last long task happens at	2.368 s
Visual Metrics
First Visual Change [median]	2.336 s
Speed Index [median]	3.390 s
Visual Complete 85% [median]	3.070 s
Visual Complete 99% [median]	7.067 s
Last Visual Change [median]	13.234 s

Timings Summary

Waterfall

Run 2 SpeedIndex median

Video

Filmstrip

Use--filmstrip.showAll to show all filmstrips.

0 s

0.6 sCPU Long Task duration 192 ms

0.8 sCPU Long Task duration 1.568 s

2.4 sFirst Visual Change 2.367 sLargest Image 2.367 sCPU Long Task duration 403 msFirst Contentful Paint 2.368 sLCP <SPAN> 2.368 s

2.5 s

2.6 s

2.7 s

2.8 s

2.9 s

3 sVisual Complete 85% 3.000 sHeading 3.000 s

3.1 sDOM Content Loaded Time 3.012 sPage Load Time 3.054 sLayout Shift 0.00069 3.059 s

3.2 sFully Loaded 3.173 s

3.3 s

3.8 s

4.3 s

4.7 s

4.8 s

5.3 s

5.8 s

6.3 s

6.7 s

6.8 s

7.1 sVisual Complete 95% 7.067 sVisual Complete 99% 7.067 s

7.2 s

7.3 s

7.7 s

7.8 s

8.3 s

8.8 s

9.3 s

9.7 s

9.8 s

10.3 s

10.8 s

11.3 s

11.7 s

11.8 s

12.3 s

12.8 s

13.3 sLast Visual Change 13.234 s

Coach

The coach helps you find performance problems on your web page using web performance best practice rules. And gives you advice on privacy and best practices. Tested using Coach-core version 8.1.1.

Coach score

• Total score 93
• Performance score 94
• Privacy score 88
• Best practice score 100

Performance advice (94)

Show/hide details

Title	Advice	Score
Avoid slowing down the critical rendering path (avoidRenderBlocking)	The page has 1 blocking requests and 1 in body parser blocking (2 JavaScript and 0 CSS).	80
Description: The critical rendering path is what the browser needs to do to start rendering the page. Every file requested inside of the head element will postpone the rendering of the page, because the browser need to do the request. Avoid loading JavaScript synchronously inside of the head (you should not need JavaScript to render the page), request files from the same domain as the main document (to avoid DNS lookups) and inline CSS for really fast rendering and a short rendering path.
Offenders: https://www.wikipedia.org/portal/wikipedia.org/assets/js/index-6bf78c58fd.js https://www.wikipedia.org/portal/wikipedia.org/assets/js/gt-ie9-ce3fe8e88d.js
Don't scale images in the browser (avoidScalingImages)	The page has 1 image that are scaled more than 100 pixels. It would be better if those images are sent so the browser don't need to scale them.	90
Description: It's easy to scale images in the browser and make sure they look good in different devices, however that is bad for performance! Scaling images in the browser takes extra CPU time and will hurt performance on mobile. And the user will download extra kilobytes (sometimes megabytes) of data that could be avoided. Don't do that, make sure you create multiple version of the same image server-side and serve the appropriate one.
Offenders: https://www.wikipedia.org/portal/wikipedia.org/assets/img/Wikipedia-logo-v2@2x.png
Have a fast first contentful paint (firstContentfulPaint)	First contentful paint can be improved (2.300 s). It is in the Google Web Vitals needs improvement range, slower than 1.8 seconds.	50
Description: The First Contentful Paint (FCP) metric measures the time from when the page starts loading to when any part of the page content is rendered on the screen. For this metric, "content" refers to text, images (including background images), <svg> elements, or non-white <canvas> elements.
Avoid CPU Long Tasks (longTasks)	The page has 3 CPU long tasks with the total of 2.223 s. The total blocking time is 484 ms and 2 long tasks before first contentful paint with total time of 1.689 s. However the CPU Long Task is depending on the computer/phones actual CPU speed, so you should measure this on the same type of the device that your user is using. Use Geckoprofiler for Firefox or Chromes tracelog to debug your long tasks.	40
Description: Long CPU tasks locks the thread. To the user this is commonly visible as a "locked up" page where the browser is unable to respond to user input; this is a major source of bad user experience on the web today. However the CPU Long Task is depending on the computer/phones actual CPU speed, so you should measure this on the same type of the device that your user is using. To debug you should use the Chrome timeline log and drag/drop it into devtools or use Firefox Geckoprofiler.
Offenders: unknown unknown unknown
Long cache headers is good (cacheHeadersLong)	The page has 5 requests that have a shorter cache time than 30 days (but still a cache time).	95
Description: Setting a cache header is good. Setting a long cache header (at least 30 days) is even better beacause then it will stay long in the browser cache. But what do you do if that asset change? Rename it and the browser will pick up the new version.
Offenders: https://www.wikipedia.org/portal/wikipedia.org/assets/img/Wikipedia-logo-v2@2x.png https://www.wikipedia.org/portal/wikipedia.org/assets/img/sprite-de847d1a.svg https://www.wikipedia.org/portal/wikipedia.org/assets/img/Wikinews-logo_sister@2x.png https://www.wikipedia.org/portal/wikipedia.org/assets/js/index-6bf78c58fd.js https://www.wikipedia.org/portal/wikipedia.org/assets/js/gt-ie9-ce3fe8e88d.js

Best practice advice (100)

Your best practice score is perfect!

Privacy advice (88)

Show/hide details

Title	Advice	Score
Use a good Content-Security-Policy header to make sure you you avoid Cross Site Scripting (XSS) attacks. (contentSecurityPolicyHeader)	Set a Content-Security-Policy header to make sure you are not open for Cross Site Scripting (XSS) attacks. You can start with setting a Content-Security-Policy-Report-Only header, that will only report the violation, not stop the download.	0
Description: Content Security Policy is delivered via a HTTP response header, and defines approved sources of content that the browser may load. It can be an effective countermeasure to Cross Site Scripting (XSS) attacks and is also widely supported and usually easily deployed. https://scotthelme.co.uk/content-security-policy-an-introduction/.
Offenders: https://www.wikipedia.org/
Set a referrer-policy header to make sure you do not leak user information. (referrerPolicyHeader)	Set a referrer-policy header to make sure you do not leak user information.	0
Description: Referrer Policy is a new header that allows a site to control how much information the browser includes with navigations away from a document and should be set by all sites. https://scotthelme.co.uk/a-new-security-header-referrer-policy/.
Offenders: https://www.wikipedia.org/

Page info

Page info
Title	Wikipedia
Width	360
Height	1690
DOM elements	1050
Avg DOM depth	9
Max DOM depth	12
Iframes	0
Script tags	4
Local storage	94 B
Session storage	0 b
Network Information API	4g

Resource Hints
preconnect
https://upload.wikimedia.org/
https://en.wikipedia.org/

Technologies used to build the page.

Data collected using Wappalyzer version 6.10.66. With updated code from Webappanalyzer 2024-12-27. Use --browsertime.firefox.includeResponseBodies htmlor --browsertime.chrome.includeResponseBodies htmlto help Wappalyzer find more information about technologies used.

Technology	Confidence	Category
HSTS	100	Security

Data from run 2

Visual Metrics

Browser Metrics

Largest Contentful Paint

When in time the page main content is rendered (collected using the Largest Contentful Paint API). Read more about Largest Contentful Paint.

Element type	SPAN
Element/tag	<span class="central-textlogo__image sprite svg-Wikipedia_wordmark"></span>
Render time	2.368 s
Element render delay	1.699 s
TTFB	421 ms
Resource delay	98 ms
Resource load duration	150 ms
Elements that needed recalculate style before LCP	1241
Time spent in recalculate style before LCP	119.974 ms
Load time	762 ms
URL	https://www.wikipedi...rite-de847d1a.svg
Size (width*height)	3750
DOM path
main > div:eq(0) > h1 > span> main > div:eq(0) > h1 > span>

The largest contentful paint is highlighted in the image. If no element is highlighted the element was removed before the screenshot or the LCP API couldn't find the element.

The Largest Contentful Paint API highlighted this image as a part of the LCP.

Detected Cumulative Layout Shift

0.00069 cumulative layout shift collected from the Cumulative Layout Shift API.

These HTML elements contribute most to the Cumulative Layout Shifts of the page. The higher score, the more layout shift.

Score	HTML Element
0.00069	<div class=" styled-select js-enabled"></div>
body#www-wikipedia-org > main > div:eq(1) > form#search-form > fieldset > div#search-input > div:eq(0)

The elements that have shifted place is highlighted in the image (that have a higher value than 0.01). If the element shifted outside of the viewport, you will not see it there. It can be hard to understand what content that has shifted, if that's the case, checkout the video or the filmstrip of the run.

Interaction to Next Paint

Interaction to Next Paint (INP) is a metric that try to measure responsiveness. It's useful if you are testing user journeys. Read more about Interaction to Next Paint.

Long Animation Frames

Read more about the Long Animation Frames API here here.

The top 10 longest animation frames entries

Server timings

Custom metrics collected through JavaScript

There are no custom configured scripts.

Extra metrics collected using scripting

There are no custom extra metrics from scripting.

Visual Elements

PageXray

How the page is built.

Largest assets on the page (by transfer size)

Requests and sizes per content type

Data per domain

Expires and last modified statistics

Requests loaded after onLoad event

Included requests done after load event end.

Requests loaded after onContentLoad

Includes requests done after DOM content loaded.

Render blocking requests

Render blocking information directly from Chrome.

Render information

CPU

Download the Chrome trace log and drag and drop it into Developer Tools / Performance in Chrome.

Long Tasks

Collected using the Long Task API. A long task is a task that take 50 milliseconds or more.

CPU last long task happened at 2.368 s

Individual Long Tasks

CPU time spent

Calculated using Tracium.

Time spent per request