Performance
· 15 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.Performance-focused optimization plan with CWV assessment, top offenders, and time estimates
First Contentful Paint First Contentful Paint — how long until the browser renders the first piece of content. Under 1.8s is good.
8.43 s
Largest Contentful Paint Largest Contentful Paint — how long until the largest visible element loads. Under 2.5s is good.
12.46 s
Total Blocking Time Total Blocking Time — total time the main thread was blocked, preventing user input. Under 200ms is good.
8.85 s
Cumulative Layout Shift Cumulative Layout Shift — measures visual stability. How much the page layout shifts during loading. Under 0.1 is good.
0.006
Speed Index Speed Index — how quickly content is visually displayed during load. Under 3.4s is good.
13.23 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.
18.47 s
Page Load Progression
FPage Weight BudgetAction9.5 MB transferred, 94 requestsFIX
Convert images to WebP/AVIF and resize to display dimensions to reduce transfer size.
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.
JavaScript bundle is large — code-split routes and lazy-load off-screen components to defer.
Source: web.dev
DThird-Party ImpactAction100% third-party, 0 ms blockingFIX
FJS Execution CostAction13252ms total JS executionFIX
Main Thread Breakdown
| Script | Total | Scripting | Parse/Compile | Party |
|---|---|---|---|---|
| https://www.wto.org/library/events/interactive_cal_code.js | 6022ms | 6015ms | 6ms | 3rd |
| https://www.wto.org/ | 5923ms | 5682ms | 2ms | 3rd |
| https://www.wto.org/library/wtomenus/common_logic_e.js | 786ms | 785ms | 1ms | 3rd |
| Unattributable | 246ms | 1ms | 0ms | 3rd |
| https://www.wto.org/cdn-cgi/challenge-platform/scripts/jsd/main.js | 139ms | 132ms | 3ms | 3rd |
| https://www.googletagmanager.com/gtag/js?id=G-4C48KGVJMD | 82ms | 64ms | 14ms | 3rd |
| https://www.wto.org/library/photo_gallery/slideshow_data.js | 55ms | 4ms | 51ms | 3rd |
DPage Weight InventoryAction94 resources · 9.5 MB · 133 KB savings availableFIX
~132.8 KiB of savings available
| # | Resource | Type | Size | Cache | Unused | 3rd party | Issues |
|---|---|---|---|---|---|---|---|
| — | — | ||||||
| 94 resources | 9.5 MiB | ||||||
DHTTP CachingActionno-store (uncacheable)FIX
no-cache, no-store, must-revalidate
| Directive | Value | Meaning |
|---|---|---|
| no-cache | — | Cache but always revalidate first |
| no-store | — | Never cache this response |
| must-revalidate | — | Must recheck with server after expiry |
CImage OptimizationAction19 images, 0 KB saveableREVIEW
Set explicit width and height to prevent CLS.
Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.
Source: web.dev / Core Web Vitals
Set explicit width and height to prevent CLS.
Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.
Source: web.dev / Core Web Vitals
Set explicit width and height to prevent CLS.
Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.
Source: web.dev / Core Web Vitals
Set explicit width and height to prevent CLS.
Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.
Source: web.dev / Core Web Vitals
Set explicit width and height to prevent CLS.
Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.
Source: web.dev / Core Web Vitals
Set explicit width and height to prevent CLS.
Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.
Source: web.dev / Core Web Vitals
Set explicit width and height to prevent CLS.
Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.
Source: web.dev / Core Web Vitals
Set explicit width and height to prevent CLS.
Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.
Source: web.dev / Core Web Vitals
Set explicit width and height to prevent CLS.
Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.
Source: web.dev / Core Web Vitals
Set explicit width and height to prevent CLS.
Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.
Source: web.dev / Core Web Vitals
Set explicit width and height to prevent CLS.
Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.
Source: web.dev / Core Web Vitals
Set explicit width and height to prevent CLS.
Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.
Source: web.dev / Core Web Vitals
Set explicit width and height to prevent CLS.
Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.
Source: web.dev / Core Web Vitals
Set explicit width and height to prevent CLS.
Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.
Source: web.dev / Core Web Vitals
Set explicit width and height to prevent CLS.
Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.
Source: web.dev / Core Web Vitals
BJS Bundles50 scripts, 133 KB unusedREVIEW
Downloaded but never executed on this page.
| Script | Size | Unused | Minified | Party |
|---|---|---|---|---|
| https://www.googletagmanager.com/gtag/js?id=G-4C48KGVJMD | 156 KB | 66 KB (42%) | ✓ | 3rd |
| https://www.wto.org/library/authentication/jquery-1.11.2.min.js | 30 KB | 22 KB (75%) | ✓ | 3rd |
| https://www.wto.org/library/authentication/jquery-1.11.2.min.js | 30 KB | 22 KB (75%) | ✓ | 3rd |
| https://www.wto.org/library/wtomenus/jquery.min.js | 30 KB | 22 KB (75%) | ✓ | 3rd |
| https://www.wto.org/library/imrdlib.js | 1 KB | — | ✓ | 3rd |
| https://www.wto.org/library/wtomenus/jkmegamenu.js | 2 KB | — | ✓ | 3rd |
| https://www.wto.org/library/wtomenus/common_data_e.js | 3 KB | — | ✓ | 3rd |
| https://www.wto.org/library/news/news_vars_e.js | 25 KB | — | ✗ | 3rd |
| https://www.wto.org/library/news/current_news_e.js | 3 KB | — | ✓ | 3rd |
| https://www.wto.org/library/news/index_news_code_e.js | 3 KB | — | ✓ | 3rd |
Consider code splitting or tree shaking to reduce unused code.
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.
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.
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.
This bundle has high unused code — code-split or tree-shake to ship only what executes.
Source: web.dev / Lighthouse coverage
A+Text CompressionAll text resources are compressedPASS
A+Font Loading5 fonts (113 KB)PASS
Web fonts
5
113 KB total
Render-blocking
0
of 5
Dominant font-display
swap
Most common across fonts
Font loading timeline
- Convert to woff2 for ~30% smaller file size
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 ~3 KB and ~6 ms
A+Resource CachingAll resources properly cachedPASS
A+Critical Rendering PathNo render-blocking resourcesPASS
A+Resource HintsNo optimization neededPASS
A+Green HostingWhether the site is served from green-energy infrastructurePASS
Green Hosting
This site is hosted on green energy infrastructure
Provider: Cloudflare
Network Waterfall94 requests over 21382msINFO
Third-Party Script CostPer-script blocking time, transfer cost, and cache headersINFO
| Script | Category | Execution | Transfer | Unused | Monthly Cost | Verdict |
|---|---|---|---|---|---|---|
www.wto.org www.wto.org | Other | 6022ms | 18 KB | — | €65/mo | Costly |
www.wto.org www.wto.org | Other | 5923ms | 11 KB | — | €64/mo | Costly |
www.wto.org www.wto.org | Other | 786ms | 4 KB | — | €9/mo | Costly |
Unattributable Unattributable | Other | 246ms | 0 KB | — | €3/mo | Costly |
www.wto.org www.wto.org | Other | 139ms | 0 KB | — | €2/mo | Optional |
Google Tag Manager www.googletagmanager.com | Tag Manager | 82ms | 156 KB | 42% | €1/mo | Optional |
www.wto.org www.wto.org | Other | 55ms | 101 KB | — | €1/mo | Optional |
These scripts may cost more than they're worth
- www.wto.org adds 6022ms and costs ~€65/month
- www.wto.org adds 5923ms and costs ~€64/month
- www.wto.org adds 786ms and costs ~€9/month
- Unattributable adds 246ms and costs ~€3/month
100% of JavaScript execution time is spent on third-party scripts. Consider auditing which scripts are essential.
When third-party JS execution time exceeds your own, performance gains from frontend work are capped by code you don't own.
Learn more ▾ ▴
Every millisecond of third-party JS competes with your own for main-thread time. If their share is bigger than yours, optimization on your code base barely moves the needle. Audit, defer, or remove third-parties before further frontend optimization. Use Lighthouse's third-party audit to identify the worst offenders.
Source: web.dev
www.wto.org takes 6022ms of CPU time. Consider loading it asynchronously or replacing it with a lighter alternative.
This script has high main-thread execution time — optimize hot paths or defer.
Source: web.dev
www.wto.org takes 5923ms of CPU time. Consider loading it asynchronously or replacing it with a lighter alternative.
This script has high main-thread execution time — optimize hot paths or defer.
Source: web.dev
www.wto.org takes 786ms of CPU time. Consider loading it asynchronously or replacing it with a lighter alternative.
This script has high main-thread execution time — optimize hot paths or defer.
Source: web.dev
Unattributable takes 246ms of CPU time. Consider loading it asynchronously or replacing it with a lighter alternative.
This script has high main-thread execution time — optimize hot paths or defer.
Source: web.dev