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https://www.economist.com

Performance

· 14 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.
SCORE
74
GRADE
C
FIX
3
REVIEW
2
PASS
7
INFO
2

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

Mobile Desktop
57
Performance Overall performance score (0–100) based on Core Web Vitals and other metrics. 90+ is good.
97
Accessibility Measures how accessible the page is for users with disabilities. Checks color contrast, ARIA labels, and semantic HTML.
77
Best Practices Checks for modern web development best practices including HTTPS, no console errors, and secure JavaScript.
100
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.

660 ms

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

5.68 s

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

25 ms

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

0.250

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

2.76 s

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

6.12 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
14
7 PASS 2 REVIEW 3 FIX
F
Page Weight Budget
Action
4.7 MB transferred, 152 requests
FIX
4.7 MB transferred, 152 requests
Critical::
Page weighs 10.0 MB (4.7 MB transferred)
Warning::
Images are 1.9 MB — compress or use modern formats
Convert images to WebP/AVIF and resize to display dimensions to reduce transfer size.
Got: 1.9 MB
Warning::
JavaScript is 1.8 MB — consider code splitting or lazy loading
Large JavaScript bundles delay interactivity. Split code by route or defer non-critical scripts.
Got: 1.8 MB
Info::
Fonts are 850 KB — consider subsetting or using system fonts
Subset fonts to include only used characters, or switch to system font stacks.
Got: 850 KB
Warning::
152 HTTP requests — consider bundling or reducing
Each request adds latency. Bundle small files, use sprites, or eliminate unnecessary requests.
Info::
Estimated 0.98 g CO2 per page load
4.7 MB / 2.4 MB budget
4.7 MB transferred
152 requests
0.98 g CO2 per page load
Images 1.9 MiB 41%
JavaScript 1.8 MiB 38%
Fonts 849.8 KiB 18%
HTML 83.9 KiB 2%
CSS 45.8 KiB 1%
Other 25.1 KiB 1%
Other 16.0 KiB 0%
Other 8.6 KiB 0%
Other 1.3 KiB 0%
Other 0 B 0%
0 2.4 MB 4.9 MB
Over budget

Convert images to WebP/AVIF and resize to display dimensions to reduce transfer size.

Why this matters

Image bandwidth is high — modern formats (WebP/AVIF) and resizing typically cut it 50%+.

Source: web.dev

Large JavaScript bundles delay interactivity. Split code by route or defer non-critical scripts.

Why this matters

JavaScript bundle is large — code-split routes and lazy-load off-screen components to defer.

Source: web.dev

Subset fonts to include only used characters, or switch to system font stacks.

Why this matters

Font payload is large — subset to used glyphs only, or fall back to system fonts (zero load time).

Source: web.dev font loading

Each request adds latency. Bundle small files, use sprites, or eliminate unnecessary requests.

Why this matters

High HTTP request count — bundling, sprite-ing, and HTTP/2 server push can reduce per-request overhead.

Source: web.dev

F
JS Bundles
Action
52 scripts, 701 KB unused
FIX
52 scripts, 701 KB unused
Warning::
https://www.economist.com/engassets/_next/static/c...: 139 KB unused (94%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://www.economist.com/engassets/_next/static/c...: 70 KB unused (71%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://www.economist.com/engassets/_next/static/c...: 66 KB unused (43%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://www.googletagmanager.com/gtag/js?id=G-WL00...: 66 KB unused (40%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://consent.economist.com/Notice.8f529.js: 61 KB unused (68%)
Consider code splitting or tree shaking to reduce unused code.
Info::
Total unused JavaScript: 701 KB
701 KB unused JavaScript

Downloaded but never executed on this page.

ScriptSizeUnusedMinifiedParty
https://www.economist.com/engassets/_next/static/chunks/bf32f307.5596899166592f66.js149 KB139 KB (94%)✓1st
https://www.economist.com/engassets/_next/static/chunks/58474bfb-8fb86143ed249a61.js99 KB70 KB (71%)✓1st
https://www.economist.com/engassets/_next/static/chunks/790-c9029d45cd705925.js156 KB66 KB (43%)✓1st
https://www.googletagmanager.com/gtag/js?id=G-WL00EXBGPS&cx=c&gtm=4e6460163 KB66 KB (40%)✓3rd
https://consent.economist.com/Notice.8f529.js91 KB61 KB (68%)✓3rd
https://www.googletagmanager.com/gtag/js?id=G-CWJ8XWVBYS166 KB61 KB (37%)✓3rd
https://www.economist.com/engassets/_next/static/chunks/pages/_app-cdfc9ac951a8fa99.js90 KB61 KB (68%)✓1st
https://www.economist.com/engassets/_next/static/chunks/7ef05774.6f38de9cd30a12ca.js100 KB58 KB (58%)✓1st
https://aswpsdkeu.com/notify/v2/ua-sdk.min.js63 KB44 KB (71%)✓3rd
https://www.economist.com/engassets/_next/static/chunks/3544.30aab8d29676792e.js49 KB33 KB (70%)✓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

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

F
HTTP Caching
Action
No cache headers
FIX
No cache headers
Warning::
No Cache-Control header found
Browsers will use heuristic caching, which can be unpredictable. Set explicit cache headers.

No Cache-Control header

Adding a Cache-Control header can significantly improve repeat-visit performance.

B
Image Optimization
49 images, 0 KB saveable
REVIEW
49 images, 0 KB saveable
Warning::
https://subscriberevents.economist.com/wp-content/... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
49 images 1.9 MB
0 oversized -0 KB
48 legacy format
1 missing dimensions CLS risk

Set explicit width and height to prevent CLS.

Why this matters

Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.

Source: web.dev / Core Web Vitals

C
JS Execution Cost
Action
1583ms total JS execution
REVIEW
1583ms total JS execution
Warning::
https://www.economist.com/: 515ms CPU time
Info::
Unattributable: 223ms CPU time
Info::
https://www.economist.com/engassets/_next/static/c...: 209ms CPU time
Info::
https://consent.economist.com/unified/wrapperMessa...: 110ms CPU time
Info::
https://consent.economist.com/Notice.8f529.js: 106ms CPU time
Info::
Third-party scripts: 673ms (43% of total)

Main Thread Breakdown

Script Evaluation 50% Style & Layout 19% Other 15% Script Parsing & Compilation 8% Rendering 5%
ScriptTotalScriptingParse/CompileParty
https://www.economist.com/515ms81ms5ms1st
Unattributable223ms8ms0ms3rd
https://www.economist.com/engassets/_next/static/chunks/framework-97862ef36bc4065f.js209ms178ms3ms1st
https://consent.economist.com/unified/wrapperMessagingWithoutDetection.js110ms89ms3ms3rd
https://consent.economist.com/Notice.8f529.js106ms82ms10ms3rd
https://consent.economist.com/index.html?hasCsp=true&message_id=1436029&consentUUID=null&consent_origin=https%3A%2F%2Fconsent.economist.com%2Fconsent%2Ftcfv2&preload_message=true&version=v199ms0ms0ms3rd
https://www.economist.com/engassets/_next/static/chunks/7632-e37ba21689ec02ef.js76ms75ms0ms1st
https://www.googletagmanager.com/gtag/js?id=G-CWJ8XWVBYS73ms63ms10ms3rd
https://www.googletagmanager.com/gtag/js?id=G-WL00EXBGPS&cx=c&gtm=4e646062ms51ms10ms3rd
https://www.economist.com/engassets/_next/static/chunks/pages/index-4eacb687c721052b.js59ms58ms1ms1st

Showing top 10 of 11 scripts

A
Third-Party Impact
39% third-party, 0 ms blocking
PASS
39% third-party, 0 ms blocking
Info::
Third-party code accounts for 39% of page weight (1.8 MiB of 4.7 MiB)
Info::
Third-party blocking time is low (0 ms)
61%
39%
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+
Font Loading
8 fonts (850 KB)
PASS
8 fonts (850 KB)
Info::
8 font(s) use font-display: swap (FOUT risk but functional)

Web fonts

8

850 KB total

Render-blocking

0

of 8

Dominant font-display

swap

Most common across fonts

Font loading timeline
Transfer FOIT (block) FOUT (swap)
0 ms 1.0 s 2.0 s 3.0 s 4.0 s 5.0 s FCP 660 ms LCP 5.7 shttps://marber-cdn.economist.com/foundations/latest/fonts/economist-sans-roman.woff2economist-sans-roman.woff2 https://marber-cdn.economist.com/foundations/latest/fonts/economist-sans-roman.woff2 — 109.1 KiB — 0 ms — font-display: swaphttps://marber-cdn.economist.com/foundations/latest/fonts/economist-serif-roman.woff2economist-serif-roman.w... https://marber-cdn.economist.com/foundations/latest/fonts/economist-serif-roman.woff2 — 97.9 KiB — 0 ms — font-display: swaphttps://marber-cdn.economist.com/foundations/latest/fonts/economist-sans-italic.woff2economist-sans-italic.w... https://marber-cdn.economist.com/foundations/latest/fonts/economist-sans-italic.woff2 — 107.7 KiB — 0 ms — font-display: swaphttps://marber-cdn.economist.com/foundations/latest/fonts/economist-serif-italic.woff2economist-serif-italic.... https://marber-cdn.economist.com/foundations/latest/fonts/economist-serif-italic.woff2 — 125.6 KiB — 0 ms — font-display: swaphttps://marber-cdn.economist.com/foundations/latest/fonts/economist-sans-headline.woff2economist-sans-headline... https://marber-cdn.economist.com/foundations/latest/fonts/economist-sans-headline.woff2 — 59.0 KiB — 0 ms — font-display: swaphttps://cdn.design-system.economist.com/assets/7.2.1/common/static/fonts/economist-sans-roman.woff2economist-sans-roman.woff2 https://cdn.design-system.economist.com/assets/7.2.1/common/static/fonts/economist-sans-roman.woff2 — 106.8 KiB — 0 ms — font-display: swaphttps://cdn.design-system.economist.com/assets/7.2.1/common/static/fonts/economist-sans-osf-roman.woff2economist-sans-osf-roma... https://cdn.design-system.economist.com/assets/7.2.1/common/static/fonts/economist-sans-osf-roman.woff2 — 107.0 KiB — 0 ms — font-display: swaphttps://marber-cdn.economist.com/foundations/latest/fonts/economist-serif-display-roman.woff2economist-serif-display... https://marber-cdn.economist.com/foundations/latest/fonts/economist-serif-display-roman.woff2 — 136.8 KiB — 0 ms — font-display: swap
economist-sans-roman.woff2 woff2 swap
Size 109 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
  • Subset this font — over 100 KB suggests Latin Extended or full glyph coverage that most pages don't need
economist-serif-roman.w... woff2 swap
Size 98 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
economist-sans-italic.w... woff2 swap
Size 108 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
  • Subset this font — over 100 KB suggests Latin Extended or full glyph coverage that most pages don't need
economist-serif-italic.... woff2 swap
Size 126 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
  • Subset this font — over 100 KB suggests Latin Extended or full glyph coverage that most pages don't need
economist-sans-headline... woff2 swap
Size 59 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
economist-sans-roman.woff2 woff2 swap
Size 107 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
  • Subset this font — over 100 KB suggests Latin Extended or full glyph coverage that most pages don't need
economist-sans-osf-roma... woff2 swap
Size 107 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
  • Subset this font — over 100 KB suggests Latin Extended or full glyph coverage that most pages don't need
economist-serif-display... woff2 swap
Size 137 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
  • Subset this font — over 100 KB suggests Latin Extended or full glyph coverage that most pages don't need
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)

Fixing the unchecked items could save ~346 KB and ~692 ms

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

Network Waterfall
152 requests over 0ms
INFO

Performance analysis not available for this result.

Third-Party Script Cost
Per-script blocking time, transfer cost, and cache headers
INFO
43% of JavaScript execution is third-party
First-party Third-party 673ms · 463KB · $9/mo
Unattributable
Other
Costly
Execution 223ms
Transfer 0 KB
Monthly Cost $3/mo
consent.economist.com
Other
Optional
Execution 110ms
Transfer 40 KB
Monthly Cost $1/mo
consent.economist.com
Other
Optional
Execution 106ms
Transfer 91 KB
Unused 68%
Monthly Cost $1/mo
consent.economist.com
Other
Optional
Execution 99ms
Transfer 2 KB
Monthly Cost $1/mo
Google Tag Manager
Tag Manager
Optional
Execution 73ms
Transfer 166 KB
Unused 37%
Monthly Cost $1/mo
Google Tag Manager
Tag Manager
Optional
Execution 62ms
Transfer 163 KB
Unused 40%
Monthly Cost $1/mo

These scripts may cost more than they're worth

  • Unattributable adds 223ms and costs ~$3/month

43% 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

Unattributable takes 223ms of CPU time. Consider loading it asynchronously or replacing it with a lighter alternative.

Why this matters

This script has high main-thread execution time — optimize hot paths or defer.

Source: web.dev

68% of consent.economist.com's code is unused. The script may be loading features you don't use.

Why this matters

Bundle has high unused-code ratio — tree-shaking and route-splitting recover the wasted bytes.

Source: web.dev

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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