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https://www.royal.uk

Performance

· 15 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.
SCORE
86
GRADE
B
FIX
0
REVIEW
4
PASS
9
INFO
2

Performance-focused optimization plan with CWV assessment, top offenders, and time estimates

Mobile Desktop
93
Performance Overall performance score (0–100) based on Core Web Vitals and other metrics. 90+ is good.
96
Accessibility Measures how accessible the page is for users with disabilities. Checks color contrast, ARIA labels, and semantic HTML.
100
Best Practices Checks for modern web development best practices including HTTPS, no console errors, and secure JavaScript.
92
SEO Measures basic SEO optimizations: meta tags, crawlability, link text, and mobile friendliness.

First Contentful Paint First Contentful Paint — how long until the browser renders the first piece of content. Under 1.8s is good.

756 ms

Largest Contentful Paint Largest Contentful Paint — how long until the largest visible element loads. Under 2.5s is good.

1.64 s

Total Blocking Time Total Blocking Time — total time the main thread was blocked, preventing user input. Under 200ms is good.

0 ms

Cumulative Layout Shift Cumulative Layout Shift — measures visual stability. How much the page layout shifts during loading. Under 0.1 is good.

0.041

Speed Index Speed Index — how quickly content is visually displayed during load. Under 3.4s is good.

756 ms

Time to Interactive Time to Interactive — how long until the page is fully interactive and responds to user input. Under 3.8s is good.

1.64 s

Page Load Progression

375 ms
750 ms
1.1 s
1.5 s
1.9 s
2.2 s
2.6 s
3.0 s
Checks
15
9 PASS 4 REVIEW
B
Page Weight Budget
1.3 MB transferred, 30 requests
REVIEW
1.3 MB transferred, 30 requests
Info::
Page weighs 2.5 MB (1.3 MB transferred)
Info::
30 HTTP requests
Info::
Estimated 0.26 g CO2 per page load
1.3 MB / 2.4 MB budget
1.3 MB transferred
30 requests
0.26 g CO2 per page load
Images 771.2 KiB 60%
JavaScript 350.9 KiB 27%
Fonts 88.1 KiB 7%
Other 44.1 KiB 3%
CSS 14.7 KiB 1%
HTML 11.0 KiB 1%
Other 938 B 0%
0 2.4 MB 4.9 MB
Under budget
B
Image Optimization
14 images, 0 KB saveable
REVIEW
14 images, 0 KB saveable
Info::
All images are well-optimized
14 images 771 KB
0 oversized -0 KB
9 legacy format
0 missing dimensions CLS risk
C
JS Bundles
Action
7 scripts, 225 KB unused
REVIEW
7 scripts, 225 KB unused
Warning::
https://www.googletagmanager.com/gtm.js?id=GTM-WBJ...: 70 KB unused (59%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://www.royal.uk/sites/default/files/js/js_sks...: 64 KB unused (70%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://www.royal.uk/sites/default/files/js/js_sks...: 64 KB unused (70%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://consent.cookiebot.com/e6cc3f6f-4a95-47e7-8...: 26 KB unused (24%)
Consider code splitting or tree shaking to reduce unused code.
Info::
Total unused JavaScript: 225 KB
225 KB unused JavaScript

Downloaded but never executed on this page.

ScriptSizeUnusedMinifiedParty
https://www.googletagmanager.com/gtm.js?id=GTM-WBJ2Q8R120 KB70 KB (59%)✓3rd
https://www.royal.uk/sites/default/files/js/js_skslNSOfxlTUCgjg_JXTTLpJ-Pa54XwbsRG2ar-Ey_A.js?scope=footer&delta=0&language=en&theme=kpp&include=eJwdjVESgyAMRC8E5khOJKmmUsIE1NLTV_Oz8_Z97CY1BrKjYp5IMOs64Ru_Ya8VMCU1Ei3eNkZic5TykiJ9xNWE3JgOzPHipUnnFj9cDveN0dL24JxUd-FFO9yrHDL-BjwRTuGrgad__wEuBjhK92 KB64 KB (70%)✓1st
https://www.royal.uk/sites/default/files/js/js_skslNSOfxlTUCgjg_JXTTLpJ-Pa54XwbsRG2ar-Ey_A.js?scope=footer&delta=0&language=en&theme=kpp&include=eJwdjVESgyAMRC8E5khOJKmmUsIE1NLTV_Oz8_Z97CY1BrKjYp5IMOs64Ru_Ya8VMCU1Ei3eNkZic5TykiJ9xNWE3JgOzPHipUnnFj9cDveN0dL24JxUd-FFO9yrHDL-BjwRTuGrgad__wEuBjhK0 KB64 KB (70%)✓1st
https://consent.cookiebot.com/e6cc3f6f-4a95-47e7-8b38-0232754863a7/cc.js?renew=false&referer=www.royal.uk&dnt=false&init=false108 KB26 KB (24%)✓3rd
https://consent.cookiebot.com/uc.js27 KB—✓3rd
https://consentcdn.cookiebot.com/consentconfig/e6cc3f6f-4a95-47e7-8b38-0232754863a7/royal.uk/configuration.js1 KB—✓3rd
https://www.royal.uk/libraries/lazysizes/lazysizes.min.js4 KB—✓1st

Consider code splitting or tree shaking to reduce unused code.

Why this matters

This bundle has high unused code — code-split or tree-shake to ship only what executes.

Source: web.dev / Lighthouse coverage

Consider code splitting or tree shaking to reduce unused code.

Why this matters

This bundle has high unused code — code-split or tree-shake to ship only what executes.

Source: web.dev / Lighthouse coverage

Consider code splitting or tree shaking to reduce unused code.

Why this matters

This bundle has high unused code — code-split or tree-shake to ship only what executes.

Source: web.dev / Lighthouse coverage

Consider code splitting or tree shaking to reduce unused code.

Why this matters

This bundle has high unused code — code-split or tree-shake to ship only what executes.

Source: web.dev / Lighthouse coverage

B
Page Weight Inventory
30 resources · 1.3 MB · 225 KB savings available
REVIEW
30 resources · 1.3 MB · 225 KB savings available
Warning::
Page weight 257 KB over 1MB target
Got: 1.3 MB Expected: ≤ 1 MB
Info::
~225 KB of savings available
Info::
13 third-party resources (23% of weight)
Info::
1 resources over 200KB
30 resources · 1.3 MiB · 13 third-party 256.9 KiB over 1MB target
Image 64% · 815.3 KiB
JavaScript 27% · 350.9 KiB
Font 7% · 88.1 KiB
CSS 1% · 14.7 KiB
Document 1% · 11.0 KiB
Other 0% · 938 B

~224.8 KiB of savings available

Remove unused JavaScript: 224.8 KiB
A
Third-Party Impact
23% third-party, 0 ms blocking
PASS
23% third-party, 0 ms blocking
Info::
Third-party code accounts for 23% of page weight (300.6 KiB of 1.3 MiB)
Info::
Third-party blocking time is low (0 ms)
77%
23%
First-party Third-party
A+
Text Compression
All text resources are compressed
PASS
All text resources are compressed
Info::
All text resources are compressed
All text resources are properly compressed.
A+
JS Execution Cost
484ms total JS execution
PASS
484ms total JS execution
Info::
https://www.royal.uk/: 243ms CPU time
Info::
Unattributable: 97ms CPU time
Info::
https://consent.cookiebot.com/e6cc3f6f-4a95-47e7-8...: 78ms CPU time
Info::
https://consent.cookiebot.com/uc.js: 66ms CPU time
Info::
Third-party scripts: 241ms (50% of total)

Main Thread Breakdown

Script Evaluation 31% Style & Layout 28% Other 24% Script Parsing & Compilation 6% Parse HTML & CSS 6% Rendering 5%
ScriptTotalScriptingParse/CompileParty
https://www.royal.uk/243ms8ms0ms1st
Unattributable97ms2ms0ms3rd
https://consent.cookiebot.com/e6cc3f6f-4a95-47e7-8b38-0232754863a7/cc.js?renew=false&referer=www.royal.uk&dnt=false&init=false78ms35ms10ms3rd
https://consent.cookiebot.com/uc.js66ms59ms4ms3rd
A+
Font Loading
2 fonts (88 KB)
PASS
2 fonts (88 KB)
Info::
2 font(s) use font-display: swap (FOUT risk but functional)

Web fonts

2

88 KB total

Render-blocking

0

of 2

Dominant font-display

swap

Most common across fonts

Font loading timeline
Transfer FOIT (block) FOUT (swap)
0 ms 500 ms 1.0 s 1.5 s FCP 756 ms LCP 1.6 shttps://fonts.gstatic.com/s/raleway/v37/1Ptug8zYS_SKggPNyC0IT4ttDfA.woff21Ptug8zYS_SKggPNyC0IT4t... https://fonts.gstatic.com/s/raleway/v37/1Ptug8zYS_SKggPNyC0IT4ttDfA.woff2 — 42.1 KiB — 12 ms — font-display: swaphttps://www.royal.uk/themes/custom/kpp/fonts/2F00DD_0_0.woff22F00DD_0_0.woff2 https://www.royal.uk/themes/custom/kpp/fonts/2F00DD_0_0.woff2 — 46.0 KiB — 21 ms — font-display: swap
1Ptug8zYS_SKggPNyC0IT4t... woff2 swap
Size 42 KB
Load time 12 ms
Start 238 ms
Risk FOUT — text flashes from fallback to web font
2F00DD_0_0.woff2 woff2 swap
Size 46 KB
Load time 21 ms
Start 239 ms
Risk FOUT — text flashes from fallback to web font
Optimization checklist
  • Preload critical fonts (priority=high)
  • Use woff2 format for all fonts
  • Set font-display to swap, optional, or fallback
  • Subset large fonts (≤100 KB each)
A+
Resource Caching
All resources properly cached
PASS
All resources properly cached
Info::
No caching issues found
All static resources have appropriate caching headers.
A+
Critical Rendering Path
No render-blocking resources
PASS
No render-blocking resources
Info::
No render-blocking resources detected
A+
Resource Hints
No optimization needed
PASS
No optimization needed
Info::
No resource hint issues
A+
Green Hosting
Whether the site is served from green-energy infrastructure
PASS

Green Hosting

This site is hosted on green energy infrastructure

Provider: Cloudflare

A+
HTTP Caching
max-age=86400 (1 day)
PASS
max-age=86400 (1 day)
Info::
Cache-Control header is set
Got: public, max-age=86400
Info::
Effective TTL: 1 day (max-age=86400)
Info::
Last-Modified header present
Cache-Control

public, max-age=86400

DirectiveValueMeaning
public—Any cache may store this response
max-age86400Cache for 1 day
Effective TTL: 86400 seconds
Network Waterfall
30 requests over 1228ms
INFO
0 ms 500 ms 1.0 s 1.5 s FCP 756 ms LCP 1.6 shttps://www.royal.uk// https://www.royal.uk/ — 200 — 10.2 KiB — 46 ms — h2https://consent.cookiebot.com/uc.jsconsent.cookiebot.com/uc.js https://consent.cookiebot.com/uc.js — 200 — 27.0 KiB — 41 ms — h2https://fonts.googleapis.com/css2?family=Raleway:ital,wght@0,400;0,500;0,700;1,400&display=swapfonts.googleapis.com/css2?family=Ra... https://fonts.googleapis.com/css2?family=Raleway:ital,wght@0,400;0,500;0,700;1,400&display=swap — 200 — 1.1 KiB — 90 ms — h2https://www.royal.uk/sites/default/files/css/css_jVeRHy8J-7kMKwoBTv1v-M6XK2Ms_G3oh988kWUnK_A.css?delta=0&language=en&theme=kpp&include=eJxVT1sOwzAIu1DTHGmiCUtR80BANvX2i9pt3X6QbYxsNmYPYhQyTtvA99YM5YAptwWyU9sz1XRIK0J8b6neqZLtLoDEfyUJnUomtc9pAaquYO0HY0jojOydKm0fSU9clAz1simChPWEG7EbRbaTtUDjomAkuOzW-EtuhTT4hBXl5wkGgSTAq_oonSHPlzL3yn0ZnVeMk-5qWPwCitOD8Kn-mHNpsWd8AadKdqs/sites/default/files/css/css_jVeRHy... https://www.royal.uk/sites/default/files/css/css_jVeRHy8J-7kMKwoBTv1v-M6XK2Ms_G3oh988kWUnK_A.css?delta=0&language=en&theme=kpp&include=eJxVT1sOwzAIu1DTHGmiCUtR80BANvX2i9pt3X6QbYxsNmYPYhQyTtvA99YM5YAptwWyU9sz1XRIK0J8b6neqZLtLoDEfyUJnUomtc9pAaquYO0HY0jojOydKm0fSU9clAz1simChPWEG7EbRbaTtUDjomAkuOzW-EtuhTT4hBXl5wkGgSTAq_oonSHPlzL3yn0ZnVeMk-5qWPwCitOD8Kn-mHNpsWd8AadKdqs — 200 — 4.9 KiB — 20 ms — h2https://www.royal.uk/sites/default/files/css/css_Kox2AllbaXpzyYfQhoimKnb8vXheL8psbuEUj39nETg.css?delta=1&language=en&theme=kpp&include=eJxVT1sOwzAIu1DTHGmiCUtR80BANvX2i9pt3X6QbYxsNmYPYhQyTtvA99YM5YAptwWyU9sz1XRIK0J8b6neqZLtLoDEfyUJnUomtc9pAaquYO0HY0jojOydKm0fSU9clAz1simChPWEG7EbRbaTtUDjomAkuOzW-EtuhTT4hBXl5wkGgSTAq_oonSHPlzL3yn0ZnVeMk-5qWPwCitOD8Kn-mHNpsWd8AadKdqs/sites/default/files/css/css_Kox2Al... https://www.royal.uk/sites/default/files/css/css_Kox2AllbaXpzyYfQhoimKnb8vXheL8psbuEUj39nETg.css?delta=1&language=en&theme=kpp&include=eJxVT1sOwzAIu1DTHGmiCUtR80BANvX2i9pt3X6QbYxsNmYPYhQyTtvA99YM5YAptwWyU9sz1XRIK0J8b6neqZLtLoDEfyUJnUomtc9pAaquYO0HY0jojOydKm0fSU9clAz1simChPWEG7EbRbaTtUDjomAkuOzW-EtuhTT4hBXl5wkGgSTAq_oonSHPlzL3yn0ZnVeMk-5qWPwCitOD8Kn-mHNpsWd8AadKdqs — 200 — 8.6 KiB — 24 ms — h2https://www.royal.uk/themes/custom/kpp/dist/images/crest-blue.svg/themes/custom/kpp/dist/images/cres... https://www.royal.uk/themes/custom/kpp/dist/images/crest-blue.svg — 200 — 57.3 KiB — 28 ms — h2https://www.royal.uk/sites/default/files/js/js_skslNSOfxlTUCgjg_JXTTLpJ-Pa54XwbsRG2ar-Ey_A.js?scope=footer&delta=0&language=en&theme=kpp&include=eJwdjVESgyAMRC8E5khOJKmmUsIE1NLTV_Oz8_Z97CY1BrKjYp5IMOs64Ru_Ya8VMCU1Ei3eNkZic5TykiJ9xNWE3JgOzPHipUnnFj9cDveN0dL24JxUd-FFO9yrHDL-BjwRTuGrgad__wEuBjhK/sites/default/files/js/js_skslNSOf... https://www.royal.uk/sites/default/files/js/js_skslNSOfxlTUCgjg_JXTTLpJ-Pa54XwbsRG2ar-Ey_A.js?scope=footer&delta=0&language=en&theme=kpp&include=eJwdjVESgyAMRC8E5khOJKmmUsIE1NLTV_Oz8_Z97CY1BrKjYp5IMOs64Ru_Ya8VMCU1Ei3eNkZic5TykiJ9xNWE3JgOzPHipUnnFj9cDveN0dL24JxUd-FFO9yrHDL-BjwRTuGrgad__wEuBjhK — 200 — 91.7 KiB — 37 ms — h2https://consentcdn.cookiebot.com/consentconfig/e6cc3f6f-4a95-47e7-8b38-0232754863a7/settings.jsonconsentcdn.cookiebot.com/consentcon... https://consentcdn.cookiebot.com/consentconfig/e6cc3f6f-4a95-47e7-8b38-0232754863a7/settings.json — 200 — 938 B — 17 ms — h2https://www.googletagmanager.com/gtm.js?id=GTM-WBJ2Q8Rwww.googletagmanager.com/gtm.js?id=... https://www.googletagmanager.com/gtm.js?id=GTM-WBJ2Q8R — 200 — 119.6 KiB — 157 ms — h2https://consentcdn.cookiebot.com/consentconfig/e6cc3f6f-4a95-47e7-8b38-0232754863a7/royal.uk/configuration.jsconsentcdn.cookiebot.com/consentcon... https://consentcdn.cookiebot.com/consentconfig/e6cc3f6f-4a95-47e7-8b38-0232754863a7/royal.uk/configuration.js — 200 — 732 B — 15 ms — h2https://consent.cookiebot.com/e6cc3f6f-4a95-47e7-8b38-0232754863a7/cc.js?renew=false&referer=www.royal.uk&dnt=false&init=falseconsent.cookiebot.com/e6cc3f6f-4a95... https://consent.cookiebot.com/e6cc3f6f-4a95-47e7-8b38-0232754863a7/cc.js?renew=false&referer=www.royal.uk&dnt=false&init=false — 200 — 108.2 KiB — 320 ms — h2https://www.royal.uk/themes/custom/kpp/dist/images/background.png/themes/custom/kpp/dist/images/back... https://www.royal.uk/themes/custom/kpp/dist/images/background.png — 200 — 445.9 KiB — 37 ms — h2data:image/svg+xml;charset=utf-8,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12.913' height='8…www.w3.org/2000/svg' width='12.913'... data:image/svg+xml;charset=utf-8,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12.913' height='8… — 200 — 0 B — 0 ms — datadata:image/svg+xml;charset=utf-8,%3Csvg xmlns='http://www.w3.org/2000/svg' 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h2https://www.royal.uk/sites/default/files/styles/grid_2x2/public/images/2023-04/Screenshot%202023-04-30%20at%206.47.34%20PM_0.png.webp?h=05f36d91&itok=nHEZrpJa/sites/default/files/styles/grid_2x... https://www.royal.uk/sites/default/files/styles/grid_2x2/public/images/2023-04/Screenshot%202023-04-30%20at%206.47.34%20PM_0.png.webp?h=05f36d91&itok=nHEZrpJa — 200 — 27.6 KiB — 22 ms — h2https://www.royal.uk/sites/default/files/styles/grid_4x2/public/images/2026-04/PA-1303311.jpg.webp?h=d5700abf&itok=BpXjWDg4/sites/default/files/styles/grid_4x... https://www.royal.uk/sites/default/files/styles/grid_4x2/public/images/2026-04/PA-1303311.jpg.webp?h=d5700abf&itok=BpXjWDg4 — 200 — 74.1 KiB — 660 ms — h2https://www.royal.uk/sites/default/files/styles/grid_4x2/public/images/feature/pa-6615625.jpg.webp?itok=GPHPl21Q/sites/default/files/styles/grid_4x... https://www.royal.uk/sites/default/files/styles/grid_4x2/public/images/feature/pa-6615625.jpg.webp?itok=GPHPl21Q — 200 — 27.0 KiB — 631 ms — h2https://www.royal.uk/sites/default/files/styles/grid_4x2/public/images/2026-04/QG_Queen_Elizabeth_LifeInStyle_QUICK_090426_09.jpg.webp?h=2bd94ce1&itok=1Lq2ey20/sites/default/files/styles/grid_4x... https://www.royal.uk/sites/default/files/styles/grid_4x2/public/images/2026-04/QG_Queen_Elizabeth_LifeInStyle_QUICK_090426_09.jpg.webp?h=2bd94ce1&itok=1Lq2ey20 — 200 — 18.4 KiB — 642 ms — h2https://www.royal.uk/sites/default/files/styles/grid_4x2/public/images/2026-04/PA-84117172.jpg.webp?h=5df9a65b&itok=a0E0BC8b/sites/default/files/styles/grid_4x... https://www.royal.uk/sites/default/files/styles/grid_4x2/public/images/2026-04/PA-84117172.jpg.webp?h=5df9a65b&itok=a0E0BC8b — 200 — 48.2 KiB — 620 ms — h2https://fonts.gstatic.com/s/raleway/v37/1Ptug8zYS_SKggPNyC0IT4ttDfA.woff2fonts.gstatic.com/s/raleway/v37/1Pt... https://fonts.gstatic.com/s/raleway/v37/1Ptug8zYS_SKggPNyC0IT4ttDfA.woff2 — 200 — 42.1 KiB — 12 ms — h3https://www.royal.uk/themes/custom/kpp/fonts/2F00DD_0_0.woff2/themes/custom/kpp/fonts/2F00DD_0_0... https://www.royal.uk/themes/custom/kpp/fonts/2F00DD_0_0.woff2 — 200 — 46.0 KiB — 21 ms — h2https://consentcdn.cookiebot.com/sdk/bc-v4.min.htmlconsentcdn.cookiebot.com/sdk/bc-v4.... https://consentcdn.cookiebot.com/sdk/bc-v4.min.html — 200 — 811 B — 17 ms — h2data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAC4AAAAuCAYAAABXuSs3AAAAAXNSR0IArs4c6QAAAARnQU1BAACxj…data:image/png;base64,iVBORw0KGgoAA... data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAC4AAAAuCAYAAABXuSs3AAAAAXNSR0IArs4c6QAAAARnQU1BAACxj… — 200 — 0 B — 0 ms — datadata:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAABIAAAASCAYAAABWzo5XAAAACXBIWXMAAAsTAAALEwEAmpwYAAAAA…data:image/png;base64,iVBORw0KGgoAA... data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAABIAAAASCAYAAABWzo5XAAAACXBIWXMAAAsTAAALEwEAmpwYAAAAA… — 200 — 0 B — 0 ms — datahttps://www.royal.uk/sites/default/files/js/js_skslNSOfxlTUCgjg_JXTTLpJ-Pa54XwbsRG2ar-Ey_A.js?scope=footer&delta=0&language=en&theme=kpp&include=eJwdjVESgyAMRC8E5khOJKmmUsIE1NLTV_Oz8_Z97CY1BrKjYp5IMOs64Ru_Ya8VMCU1Ei3eNkZic5TykiJ9xNWE3JgOzPHipUnnFj9cDveN0dL24JxUd-FFO9yrHDL-BjwRTuGrgad__wEuBjhK/sites/default/files/js/js_skslNSOf... https://www.royal.uk/sites/default/files/js/js_skslNSOfxlTUCgjg_JXTTLpJ-Pa54XwbsRG2ar-Ey_A.js?scope=footer&delta=0&language=en&theme=kpp&include=eJwdjVESgyAMRC8E5khOJKmmUsIE1NLTV_Oz8_Z97CY1BrKjYp5IMOs64Ru_Ya8VMCU1Ei3eNkZic5TykiJ9xNWE3JgOzPHipUnnFj9cDveN0dL24JxUd-FFO9yrHDL-BjwRTuGrgad__wEuBjhK — 200 — 0 B — 7 ms — h2https://www.royal.uk/themes/custom/kpp/favicon.png/themes/custom/kpp/favicon.png https://www.royal.uk/themes/custom/kpp/favicon.png — 200 — 44.1 KiB — 20 ms — h2https://www.royal.uk/libraries/lazysizes/lazysizes.min.js/libraries/lazysizes/lazysizes.min.... https://www.royal.uk/libraries/lazysizes/lazysizes.min.js — 200 — 3.5 KiB — 23 ms — h2https://www.royal.uk/sites/default/files/styles/grid_4x2/public/images/2026-03/PA-83939500.jpg.webp?h=6d295dbf&itok=gqckI6EE/sites/default/files/styles/grid_4x... https://www.royal.uk/sites/default/files/styles/grid_4x2/public/images/2026-03/PA-83939500.jpg.webp?h=6d295dbf&itok=gqckI6EE — 200 — 30.9 KiB — 616 ms — h2
HTML JavaScript CSS Images Fonts XHR/Fetch Other
Third-Party Script Cost
Per-script blocking time, transfer cost, and cache headers
INFO
50% of JavaScript execution is third-party
First-party Third-party 241ms · 135KB · £2/mo
Unattributable
Other
Optional
Execution 97ms
Transfer 0 KB
Monthly Cost £1/mo
consent.cookiebot.com
Other
Optional
Execution 78ms
Transfer 108 KB
Unused 24%
Monthly Cost £1/mo
consent.cookiebot.com
Other
Optional
Execution 66ms
Transfer 27 KB
Monthly Cost £1/mo

50% of JavaScript execution time comes from third-party scripts.

Why this matters

Third-party scripts (analytics, ads, social, A/B testing) often dominate execution time — every one is a perf-and-privacy tax.

Learn more ▾

Each third-party script is a black box: you don't control when it loads, what it executes, or how much it grows. They often account for a major share of total blocking time on average sites (HTTP Archive's Web Almanac documents the trend). Audit which ones you actually need, defer the rest, and use facade patterns (lite-youtube, lite-vimeo) for embedded media.

Source: web.dev / HTTP Archive Web Almanac

How third-party costs are calculated

All checks on this page are automated. Results are estimates - run targeted manual reviews when the score affects a release decision.

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