Run 1 summary

https://skin.healnova.ai

Tested 2026-08-06 13:59:22 using Chrome 150.0.7871.186 (runtime settings)

SummaryWaterfallMetricsRenderingCoachPageXrayThird party

Summary

Google Web Vitals

785 msTTFB
996 msLargest Contentful Paint
0.000Cumulative Layout Shift

Loading

996 msFirst Paint
1.689 sFully Loaded

Page weight & requests

18.2 KBTotal transfer size
43.6 KBTotal content size
5Requests

CPU

1Long tasks
924 msLast long task at

Visual progress

1.033 sFirst Visual Change
1.033 sSpeed Index
1.033 sVisual Complete 85%
1.033 sVisual Complete 99%
1.033 sLast Visual Change
Screenshot
Run 1 · after page complete

Waterfall

First paintFCPLCPDOMContentLoadedDOM interactiveLoadRender-blockingRedirectError

Rendering

Run 1
0.000 s
0s0.5s1s

The red band on the timeline marks when the main thread was busy with long tasks: moments when the page could not paint or respond, however the video looks.

Download video

Filmstrip

4 frames

Use --filmstrip.showAll to show all filmstrips.

Frame at 0 ms
0 ms
0 %
Frame at 900 ms
900 ms
0 %
Frame at 1.000 s
1.000 s
0 %
Frame at 1.100 s
1.100 s
100 %

Click a frame to seek the video to that moment. The dot marks frames where the page changed visually.

Why was rendering delayed?

Rendering was not meaningfully delayed. First paint landed at 996 ms on a 785 ms first byte, with no render-blocking requests: the ~199 ms after the document is style and layout work.

Want to see how much CSS style-recalculation work delayed FCP and LCP, plus CPU long tasks? Run with --cpu.

Render blocking requests

0 requests

Blocking requests delay both paints: the browser renders nothing until they arrive, so they push First Contentful Paint and everything after it, including the largest paint (LCP). Requests that block the parser inside the body stall everything after them in the document. Load JavaScript with defer or async, and keep non-critical CSS off the critical path with media attributes. Bars show when each request loaded on a clock that runs to the last paint; the gap after the bars is style and layout work.

None. Nothing except the document itself blocked rendering.

RequestWhen it loadedTransferDownload
document
skin.healnova.ai · TTFB 785 ms
797 ms
6.2 KB796 ms
0249 ms498 msFCP · LCP 996 ms

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 9.2.1.

Performance advice

98
1 error3 warnings1 info
warn(80)Avoid CPU Long TaskslongTasks

The page has 1 CPU long task with the total of 200 ms. The total blocking time is 0 ms and 1 long task before first contentful paint with total time of 200 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.

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
  • same-origin-descendant
warn(90)Avoid doing redirectsassetsRedirects

The page has 1 redirect. 1 of the redirects are from the base domain, please fix them!

A redirect is one extra step for the user to download the asset. Avoid that if you want to be fast. Redirects are even more of a showstopper on mobile.

Offenders
warn(90)Always compress text contentcompressAssets

The page has 1 request that are served uncompressed. You could save a lot of bytes by sending them compressed instead.

In the early days of the Internet there were browsers that didn't support compressing (gzipping) text content. They do now. Make sure you compress HTML, JSON, JavaScript, CSS and SVG. It will save bytes for the user; making the page load faster and use less bandwith.

Offenders
URLTransferContent
https://skin.healnova.ai/cdn-cgi/challenge-platform/h/b/scripts/jsd/8eb6d5cd556e/main.js?9.6 KB20.1 KB
error(90)Avoid missing and error requestsresponseOk

The page has 1 error response. The page has 1 response with code 404.

Your page should never request assets that return a 400 or 500 error. These requests are never cached. If that happens something is broken. Please fix it.

Offenders
infoLong cache headers is goodcacheHeadersLong

The page has 3 requests that have a shorter cache time than one year (but still a cache time).

Setting a cache header is good. Setting a long cache header (a year) is even better because the asset will stay in the browser cache across visits. For content-hashed URLs (e.g. app.4af2.css) you can safely use Cache-Control: max-age=31536000, immutable. For unversioned URLs that may change, use a revalidating strategy instead.

Offenders

Best practice advice

89
4 info
infoMeta descriptionmetaDescription

The page is missing a meta description.

Use a page description to make the page more relevant to search engines.

infoGive every image a textual alternativeimageAltText

The page has 1 image without an alt attribute. Add alt="..." with a description, or alt="" if the image is purely decorative.

Every <img> needs an alt attribute. Use alt="meaningful description" for content images so assistive technologies can announce them, or alt="" (or role="presentation" / aria-hidden="true") for purely decorative images so they are skipped. A missing alt attribute leaves screen reader users with no information at all. https://developer.mozilla.org/en-US/docs/Web/HTML/Element/img#alt

Offenders
infoAvoid unnecessary headersunnecessaryHeaders

There are 5 responses that sets a server header.

Do not send headers that you don't need. We look for p3p, cache-control and max-age, pragma, server and x-frame-options headers. Have a look at Andrew Betts - Headers for Hackers talk as a guide https://www.youtube.com/watch?v=k92ZbrY815c or read https://www.fastly.com/blog/headers-we-dont-want.

Offenders
infoDo not send too long headerslongHeaders

https://skin.healnov.../a26e8fd1ee8569ae has a header cf-chl-out-s that is 1713 characters long.

Do not send response headers that are too long.

Offenders

Privacy advice

69
1 error6 warnings2 info
warn(0)Declare a referrer policy on the documentreferrerPolicy

No <meta name="referrer"> tag was found on the page. Set a Referrer-Policy response header (preferred) or add a meta tag, for example <meta name="referrer" content="strict-origin-when-cross-origin">.

Without an explicit referrer policy the browser falls back to the user-agent default and may leak the full URL of the previous page (including query strings) to every cross-origin request. Set a Referrer-Policy response header (preferred) or a <meta name="referrer"> tag in the document. https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Referrer-Policy

warn(0)Use a strict Content-Security-Policy header to mitigate cross-site scripting (XSS) attacks.contentSecurityPolicyHeader

Set a Content-Security-Policy header to mitigate cross-site scripting attacks. You can start with a Content-Security-Policy-Report-Only header, which only reports violations rather than blocking them.

A Content-Security-Policy response header tells the browser which sources of script, style, and other content are allowed. The most effective form is a strict CSP using nonces or hashes together with strict-dynamic; the worst is a missing header, with unsafe-inline and unsafe-eval close behind. https://web.dev/articles/strict-csp

Offenders
infoSet a Cross-Origin-Embedder-Policy header so cross-origin subresources opt in to being embedded.crossOriginEmbedderPolicyHeader

Set a Cross-Origin-Embedder-Policy header (typically require-corp or credentialless) on the document response to control cross-origin embedding.

Cross-Origin-Embedder-Policy (COEP) makes the page refuse to load cross-origin subresources unless they explicitly opt in via CORP or CORS. Together with Cross-Origin-Opener-Policy it puts the page in a cross-origin isolated context, which mitigates cross-window side-channel attacks (Spectre) and unlocks high-resolution timers and SharedArrayBuffer. https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Cross-Origin-Embedder-Policy

Offenders
warn(0)Set a Cross-Origin-Opener-Policy header to isolate the page from cross-origin windows.crossOriginOpenerPolicyHeader

Set a Cross-Origin-Opener-Policy header (typically same-origin) on the document response to isolate the page from cross-origin windows.

Cross-Origin-Opener-Policy (COOP) lets a page sever its window-group ties to cross-origin documents that opened it or that it opens. Together with Cross-Origin-Embedder-Policy it puts the page in a cross-origin isolated context, which mitigates cross-window side-channel attacks (Spectre) and unlocks high-resolution timers and SharedArrayBuffer. https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Cross-Origin-Opener-Policy

Offenders
infoSet a Cross-Origin-Resource-Policy header to limit who may embed the page.crossOriginResourcePolicyHeader

Set a Cross-Origin-Resource-Policy header (same-origin, same-site or cross-origin) on the document response to limit who may embed it.

Cross-Origin-Resource-Policy (CORP) is a per-response opt-in that tells the browser which origins are allowed to embed the resource. It blocks cross-origin or cross-site no-cors embedding (img, script, iframe, etc.) and is one of the building blocks of cross-origin isolation. https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Cross-Origin-Resource-Policy

Offenders
warn(0)Set a Permissions-Policy header to control which browser features the page can use.permissionsPolicyHeader

Set a Permissions-Policy header to control which browser features the page can use.

The Permissions-Policy response header (the successor to Feature-Policy) lets a site explicitly opt in or out of powerful browser features such as camera, microphone, geolocation, payment and clipboard. Setting a strict policy reduces the attack surface and limits what embedded third parties can do. https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Permissions-Policy

Offenders
warn(0)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.

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
error(0)Set a strict transport header to make sure the user always use HTTPS.strictTransportSecurityHeader

Set a strict transport header to make sure the user always use HTTPS.

The HTTP Strict-Transport-Security response header (often abbreviated as HSTS) lets a web site tell browsers that it should only be accessed using HTTPS, instead of using HTTP. https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Strict-Transport-Security.

Offenders
warn(0)Set X-Content-Type-Options: nosniff to stop the browser from MIME-sniffing the response.xContentTypeOptionsHeader

Set X-Content-Type-Options: nosniff on the document response to prevent MIME-sniffing.

X-Content-Type-Options: nosniff prevents browsers from interpreting files as a different MIME type than what is declared in the Content-Type header. This blocks a class of cross-site scripting and content-type confusion attacks and should be set on every response. https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/X-Content-Type-Options

Offenders

Page info

A snapshot of what the browser actually built for this page: the document, how big and deep the DOM tree is and what it kept in storage. Big, deep trees are slower to style and lay out, so the counts Chrome warns about carry a flag.

Page info

Document

What the page says it is and how large it rendered.

TitleReal-time Melanoma DetectionThe document title, shown in the browser tab and used by search results.
Layout viewport1350 × 738 pxThe width the page laid out at, and the full height of the rendered document.

DOM structure

How much markup the browser has to build, style and lay out.

DOM elements38Total HTML elements. Fewer means less for the browser to style, lay out and paint.
Avg DOM depth4How deeply elements are nested on average.
Max DOM depth6The deepest nesting on the page. Deep branches cost more style recalculation.
Iframes1Embedded documents. Each is a separate page the browser loads and renders.
Script tags2Number of script elements. More scripts usually means more main-thread work.

Storage and connection

What the page stored on the client, and the network it was tested on.

Local storage0 bData the page saved in localStorage, kept across visits.
Session storage0 bData kept in sessionStorage for this tab session only.
Connection type4GWhat the Network Information API reported for the test connection.

Technologies used to build the page

Data collected using Coach-core version 9.2.1. With updated code from Webappanalyzer 2026-05-04. Use --browsertime.firefox.includeResponseBodies html or --browsertime.chrome.includeResponseBodies html to help Wappalyzer find more information about technologies used.

Detected technologies

2 technologies

Visual Metrics

Visual milestones

all times from navigation start
Speed Index1.03 show quickly the page looked done
First Visual Change1.03 sfirst paint reaches the screen
Last Visual Change1.03 sscreen stops changing
nothing painted yet
First Visual Change · Visual Complete 85% · Visual Complete 95% · Visual Complete 99% · Last Visual Change1.03 s
00.2 s0.4 s0.6 s0.8 s
Content milestones
Perception index
Visual progress
Visual progress at 0 s0.0s
Visual progress at 0.9 s0.9s
Visual progress at 1 s1.0s
Visual progress at 1.1 s1.1s
FCP1.00s
LCP1.00s
VC851.03s
Long tasks
0.0s0.2s0.4s0.7s0.9s1.1s

Google Web Vitals

Largest Contentful Paint

When the page main content is rendered, collected via the Largest Contentful Paint API. Read more about Largest Contentful Paint.

996 msLCP render time

Phase breakdown

  • TTFB785 ms
  • Resource load delay0 ms
  • Resource load duration0 ms
  • Element render delay212 ms

Element

Element type
<h1>
Size (w × h)
16776
Load time
0 ms

DOM path

body > div > h1
LCP

The LCP element is highlighted in the screenshot. If nothing is highlighted the element was removed before the screenshot or the LCP API couldn't find it.

Cumulative Layout Shift

How much the page's content shifts as it loads, collected via the Cumulative Layout Shift API.

0.000cumulative layout shift score

No layout shifts were detected on this page.

Browser Metrics

Navigation Timing
Extra timings

Server timings

Timing data the server chose to expose through Server-Timing response headers on the main document — typically backend time, cache status or experiment flags.

Server timings

1 entry
NameDurationDescription
cfExtPri0 ms

Custom metrics collected through JavaScript

There are no custom configured scripts.

Extra metrics collected using scripting

There are no custom extra metrics from scripting.

Chrome internal metrics (CDP)33
Audio handlers0
Audio worklet processors0
Documents10
Frames9
JS event listeners9
Layout objects61
Media key sessions0
Media keys0
Nodes300
Resources3
Context lifecycle state observers20
V8 per context datas5
Worker global scopes0
Uacss resources0
Rtc peer connections0
Resource fetchers10
Ad subframes0
Detached script states3
Array buffer contents3
Layout count4
Recalc style count8
Layout duration31
Recalc style duration13
Dev tools command duration15
Script duration214
V8 compile duration1
Task duration320
Task other duration46
Thread time0
Process time0
JS heap used size5331208
JS heap total size10625024
First meaningful paint992

PageXray

How the page is built.

HTTP versionH3
Total requests5
Total domains1
Transfer size18.2 KB
Content size43.6 KB
Missing compression1
Cookies10 third-party

Main document

status 200 · 0 redirects

https://skin.healnova.ai/

HeaderValue
alt-svch3=":443"; ma=86400
cf-cache-statusDYNAMIC
cf-raya26e8fd1ee8569ae-BOM
content-encodingzstd
content-typetext/html; charset=utf-8
dateThu, 06 Aug 2026 13:59:23 GMT
nel{"report_to":"cf-nel","success_fraction":0.0,"max_age":604800}
priorityu=0,i
report-to{"group":"cf-nel","max_age":604800,"endpoints":[{"url":"https://a.nel.cloudflare.com/report/v4?s=AX1D%2FdI5w80aRirqxxFtXFds%2F7nmigTIb9RFaQx5fc65vXWI6Mn45LSyBH8UP%2BTR77rKAPFqkn5ZRXrH%2FYoVQdMJJMaYadBtIRF6GtmgE1B8y43W8msDGeFPeDiGtB5OSZBB"}]}
servercloudflare
server-timingcfExtPri

Response codes

200
360.0%
302
120.0%
404
120.0%

Largest assets on the page (by transfer size)

5 assets

Requests and sizes per content type

3 types

Transfer size17.8 KB

  • javascript54.1%
  • html34.9%
  • plain11.0%

Content size43.6 KB

  • html53.9%
  • javascript46.1%

Requests3

  • html33.3%
  • javascript33.3%
  • plain33.3%
ContentHeader SizeTransfer SizeContent SizeRequests
html0 b6.2 KB23.5 KB1
javascript0 b9.6 KB20.1 KB1
plain0 b1.9 KB0 b1
Total0 b17.8 KB43.6 KB3

Data per domain

1 domain
DomainTotal download timeTransfer SizeContent SizeRequests
skin.healnova.ai1.658 s18.2 KB43.6 KB5

Expires & last-modified statistics

typeminmedianmax
Expires0 seconds5 minutes4 hours

Requests loaded after onLoad event

4 requests

Includes requests done after load event end.

ContentTransfer SizeRequests
html0 b0
css0 b0
javascript9.6 KB1
image0 b0
font0 b0
favicon0 b0
plain1.9 KB1
Total12.0 KB4

Requests loaded after onContentLoad

4 requests

Includes requests done after DOM content loaded.

ContentTransfer SizeRequests
html0 b0
css0 b0
javascript9.6 KB1
image0 b0
font0 b0
favicon0 b0
plain1.9 KB1
Total12.0 KB4

Third party

Third party requests categorised by Third party web version 0.29.2.

No third-party requests detected

Every request on this page resolved to a first-party domain. There are no entries in Third party web to attribute, no third-party tools to enumerate, and no third-party cookies set. If you expected to see entries here you can fine-tune the first-party domain list with --firstParty.

First party requests and sizes per content type

5 requests

Calculated using .*healnova.* (use --firstParty to configure).

ContentHeader SizeTransfer SizeContent SizeRequests
html0 b6.2 KB23.5 KB1
css0 b0 b0 b0
javascript0 b9.6 KB20.1 KB1
image0 b0 b0 b0
font0 b0 b0 b0
favicon0 b0 b0 b0
plain0 b1.9 KB0 b1
TotalN/A18.2 KB43.6 KB5