Run 3 summary

https://www.wikipedia.org

Tested 2025-06-18 13:58:30 using Chrome 137.0.7151.55 (runtime settings).

SummaryWaterfall MetricsVideoFilmstrip CoachPageXrayCPU Screenshots

Summary

MetricValue
Page metrics
Performance score96
Total page size94.9 KB
Requests7
Timing metrics
TTFB438 ms
First Paint880 ms
Fully Loaded3.148 s
Google Web Vitals
TTFB438 ms
First Contentful Paint (FCP) 880 ms
Largest Contentful Paint (LCP) 880 ms
Cumulative Layout Shift (CLS) 0.00
Total Blocking Time1.848 s
Max Potential FID1.558 s
CPU metrics
CPU long tasks3
CPU last long task happens at2.471 s
Visual Metrics
First Visual Change900 ms
Speed Index2.750 s
Visual Complete 85%7.067 s
Visual Complete 99%7.067 s
Last Visual Change12.800 s
Screenshot
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Waterfall

| Video | Download | 

Video

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| Filmstrip | 

Filmstrip

Use--filmstrip.showAll to show all filmstrips.

0 s
0.6 sCPU Long Task duration 267 ms
0.9 sFirst Contentful Paint 880 msLCP <SPAN> 880 msCPU Long Task duration 1.558 sFirst Visual Change 900 msLargest Image 900 ms
1 s
1.1 s
1.2 s
1.3 s
1.4 s
1.5 s
1.6 s
1.7 s
1.8 s
2.5 sCPU Long Task duration 390 ms
3 sHeading 2.967 sDOM Content Loaded Time 2.989 s
3.1 sPage Load Time 3.032 sLayout Shift 0.00069 3.037 s
3.2 sFully Loaded 3.148 s
3.3 s
3.4 s
3.5 s
3.6 s
3.7 s
3.8 s
4.3 s
4.4 s
4.8 s
5.3 s
5.4 s
5.7 s
5.8 s
6.3 s
6.4 s
6.8 s
7.1 sVisual Complete 85% 7.067 sVisual Complete 95% 7.067 sVisual Complete 99% 7.067 s
7.2 s
7.3 s
7.8 s
8.3 s
8.4 s
8.8 s
9.3 s
9.8 s
10.3 s
10.4 s
10.8 s
11.3 s
11.8 s
12.3 s
12.4 s
12.8 sLast Visual Change 12.800 s
| Performance advice | Best practice advice | Privacy advice | Page info | Technologies | 

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.

I am the coach

Coach score

Performance advice (96)

TitleAdviceScore
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
  • Avoid CPU Long Tasks (longTasks)The page has 3 CPU long tasks with the total of 2.215 s. The total blocking time is 1.848 s and 1 long task before first contentful paint with total time of 267 ms. 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/js/index-6bf78c58fd.js
  • https://www.wikipedia.org/portal/wikipedia.org/assets/js/gt-ie9-ce3fe8e88d.js
  • https://www.wikipedia.org/portal/wikipedia.org/assets/img/Wikinews-logo_sister@2x.png
  • Best practice advice (100)

    Your best practice score is perfect!

    Privacy advice (88)

    TitleAdviceScore
    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
    TitleWikipedia
    Width360
    Height1690
    DOM elements1050
    Avg DOM depth9
    Max DOM depth12
    Iframes0
    Script tags4
    Local storage94 B
    Session storage0 b
    Network Information API4g
    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.

    TechnologyConfidenceCategory
    HSTS 100  Security
    | Browser metrics | Visual Metrics | Largest Contentful Paint | Cumulative Layout Shift | Long Aninimation Frames | Visual Elements | Metrics from CDP | Server timings | 

    Visual Metrics

    Browser Metrics

    Google Web Vitals
    Time to first byte (TTFB)438 ms
    First Contentful Paint (FCP)880 ms
    Largest Contentful Paint (LCP)880 ms
    Cumulative Layout Shift (CLS)0.00
    Total Blocking Time (TBT)1.848 s
    First Contentful Paint info
    Elements that needed recalculate style before FCP359
    Time spent in recalculate style before FCP39.252 ms
    Extra timings
    TTFB438 ms
    First Paint880 ms
    Load Event End3.032 s
    Fully loaded3.148 s

    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 typeSPAN
    Element/tag<span class="central-textlogo__image sprite svg-Wikipedia_wordmark"></span>
    Render time 880 ms
    Element render delay190 ms
    TTFB438 ms
    Resource delay89 ms
    Resource load duration163 ms
    Elements that needed recalculate style before LCP359
    Time spent in recalculate style before LCP39.252 ms
    Load time839 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>
    LCP

    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.

    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.

    ScoreHTML 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)
    Layout shift

    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.

    Long Animation Frames

    Read more about the Long Animation Frames API here here.

    The top 10 longest animation frames entries

    Blocking duration Work durationRender durationPreLayout DurationStyle And Layout Duration
    1.499 s1.554 s5.8 ms4.3 ms1.5 ms
    No availible script information.
    Blocking duration Work durationRender durationPreLayout DurationStyle And Layout Duration
    323 ms389.1 ms6.2 ms6.1 ms0.1 ms
    No availible script information.
    Blocking duration Work durationRender durationPreLayout DurationStyle And Layout Duration
    230.3 ms78.2 ms260.4 ms258.3 ms2.1 ms
    No availible script information.
    Blocking duration Work durationRender durationPreLayout DurationStyle And Layout Duration
    0 ms57.4 ms2.4 ms2.4 ms0 ms
    No availible script information.
    Blocking duration Work durationRender durationPreLayout DurationStyle And Layout Duration
    0 ms75.9 ms3.9 ms3.8 ms0.1 ms
    https://www.wikipedia.org/portal/wikipedia.org/assets/js/index-6bf78c58fd.js

    Invoker:  https://www.wikipedia.org/portal/wikipedia.org/assets/js/index-6bf78c58fd.js
    Invoker Type: classic-script
    Window attribution: self

    Blocking duration Work durationRender durationPreLayout DurationStyle And Layout Duration
    0 ms48.3 ms2 ms0.2 ms1.8 ms
    https://www.wikipedia.org/portal/wikipedia.org/assets/js/index-6bf78c58fd.js

    Invoker:  #document.onDOMContentLoaded
    Invoker Type: event-listener
    Source Function Name:  t
    Window attribution: self
    Source char position: 38

    Server timings

    namedurationdescription
    cache0hit-front
    host0cp3067

    Custom metrics collected through JavaScript

    There are no custom configured scripts.

    Extra metrics collected using scripting

    There are no custom extra metrics from scripting.

    CDP Performance

    namevalue
    AudioHandlers0
    AudioWorkletProcessors0
    Documents6
    Frames2
    JSEventListeners27
    LayoutObjects1783
    MediaKeySessions0
    MediaKeys0
    Nodes3369
    Resources6
    ContextLifecycleStateObservers13
    V8PerContextDatas3
    WorkerGlobalScopes0
    UACSSResources0
    RTCPeerConnections0
    ResourceFetchers6
    AdSubframes0
    DetachedScriptStates2
    ArrayBufferContents1
    LayoutCount10
    RecalcStyleCount10
    LayoutDuration2048
    RecalcStyleDuration174
    DevToolsCommandDuration232
    ScriptDuration53
    V8CompileDuration4
    TaskDuration2898
    TaskOtherDuration387
    ThreadTime14
    ProcessTime16
    JSHeapUsedSize2115596
    JSHeapTotalSize3543040
    FirstMeaningfulPaint2447

    Visual Elements

    NameDisplay TimeX YWidthHeight
    LargestImage (Wikipedia-logo-v2.png)900 ms 69 45 57 52
    <img class="central-featured-logo" src="portal/wikipedia.org/assets/img/Wikipedia-logo-v2.png" srcset="portal/wikipedia.org/assets/img/Wikipedia-logo-v2@1.5x.png 1.5x, portal/wikipedia.org/assets/img/Wikipedia-logo-v2@2x.png 2x" width="200" height="183" alt="">
    Heading2.967 s 129 44 152 53
    <h1 class="central-textlogo-wrapper"></h1>
    LargestContentfulPaint900 ms 131 47 150 25
    <span class="central-textlogo__image sprite svg-Wikipedia_wordmark"></span>
    | Summary  | Largest responses  | Requests and sizes per content type  | Data per domain | Expires and last modified statistics  | Console log  | Requests loaded after onLoad event  | Render blocking requests  | 

    PageXray

    How the page is built.

    Summary
    HTTP versionHTTP/2.0
    Total requests7
    Total domains1
    Total transfer size94.9 KB
    Total content size203.8 KB
    Responses missing compression3
    Number of cookies3
    Third party cookies0
    Requests per response code
    2007

    Largest assets on the page (by transfer size)

    Requests and sizes per content type

    ContentHeader SizeTransfer SizeContent SizeRequests
    html0 b23.0 KB89.3 KB1
    javascript0 b9.9 KB22.5 KB2
    image0 b41.6 KB39.9 KB2
    svg0 b18.8 KB49.4 KB1
    favicon0 b1.8 KB2.7 KB1
    Total0 b94.9 KB203.8 KB7

    Data per domain

    DomainTotal download timeTransfer SizeContent SizeRequests
    www.wikipedia.org1.353 s94.9 KB203.8 KB7

    Expires and last modified statistics

    typeminmedianmax
    Expires1 hour1 day1 year
    Last modified23 hours13 weeks13 weeks

    Console log

    No console log messages.

    Requests loaded after onLoad event

    Included requests done after load event end.

    ContentTransfer SizeRequests
    html0 b0
    css0 b0
    javascript0 b0
    image0 b0
    font0 b0
    favicon1.8 KB1
    Total1.8 KB1

    Requests loaded after onContentLoad

    Includes requests done after DOM content loaded.

    ContentTransfer SizeRequests
    html0 b0
    css0 b0
    javascript0 b0
    image0 b0
    font0 b0
    favicon1.8 KB1
    Total1.8 KB1

    Render blocking requests

    Render blocking information directly from Chrome.

    BlockingIn body parser blockingPotentially blocking
    110

    Render information

    CPU Long Tasks | CPU Time Spent | CPU Time Spent Per Request | 

    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.

    TypeQuantityTotal duration (ms)
    Total Blocking Time 1848
    Max Potential First Input Delay 1558
    Long Tasks before First Paint1267
    Long Tasks before First Contentful Paint1267
    Long Tasks before Largest Contentful Paint1267
    Long Tasks after Load Event End00
    Total Long Tasks32215

    CPU last long task happened at 2.471 s

    Individual Long Tasks

    namestartTimedurationcontainerIdcontainerNamecontainerSrccontainerType
    unknown520267window
    unknown8891558window
    unknown2471390window

    CPU time spent

    Calculated using Tracium.

    Categories (ms)
    parseHTML49
    styleLayout2249
    paintCompositeRender36
    scriptParseCompile4
    scriptEvaluation76
    garbageCollection0
    other398
    Events (ms)
    Layout2057
    RunTask218
    UpdateLayoutTree191
    CpuProfiler::StartProfiling79
    ParseHTML48
    v8.run39
    PrePaint22
    Paint22
    DecodedDataDocumentParser::AppendBytes21
    RunMicrotasks16
    PaintImage11
    FunctionCall10

    Time spent per request

    URLCPU time (ms)
    https://www.wikipedia.org/portal/wikipedia.org/assets/js/index-6bf78c58fd.js44
    afterPageCompleteCheck.jpg | layoutShift.jpg | largestContentfulPaint.jpg | 

    Screenshots

    afterPageCompleteCheck.jpg

    afterPageCompleteCheck.jpg

    layoutShift.jpg

    layoutShift.jpg

    largestContentfulPaint.jpg

    largestContentfulPaint.jpg