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.
1.07 s
Largest Contentful Paint Largest Contentful Paint — how long until the largest visible element loads. Under 2.5s is good.
2.44 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.
0.443
Speed Index Speed Index — how quickly content is visually displayed during load. Under 3.4s is good.
1.16 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.
2.49 s
Page Load Progression
DPage Weight BudgetAction2.3 MB transferred, 63 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
DThird-Party ImpactAction100% third-party, 0 ms blockingFIX
DPage Weight InventoryAction63 resources · 2.3 MB · 37 KB savings availableFIX
~37.3 KiB of savings available
| # | Resource | Type | Size | Cache | Unused | 3rd party | Issues |
|---|---|---|---|---|---|---|---|
| — | — | ||||||
| 63 resources | 2.3 MiB | ||||||
FHTTP CachingActionNo cache headersFIX
No Cache-Control header
Adding a Cache-Control header can significantly improve repeat-visit performance.
CImage OptimizationAction15 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
CGreen HostingActionWhether the site is served from green-energy infrastructureREVIEW
Green Hosting
No green hosting detected
A+Text CompressionAll text resources are compressedPASS
A+JS Execution Cost285ms total JS executionPASS
Main Thread Breakdown
| Script | Total | Scripting | Parse/Compile | Party |
|---|---|---|---|---|
| https://www.cnr.it// | 114ms | 2ms | 1ms | 3rd |
| Unattributable | 91ms | 1ms | 0ms | 3rd |
| https://www.cnr.it/sites/all/modules/contrib/jquery_update/replace/jquery/1.9/jquery.min.js?v=1.9.1 | 81ms | 51ms | 3ms | 3rd |
A+Font Loading4 fonts (130 KB)PASS
Web fonts
4
130 KB total
Render-blocking
0
of 4
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 ~7 KB and ~14 ms
AJS Bundles29 scripts, 37 KB unusedPASS
Downloaded but never executed on this page.
| Script | Size | Unused | Minified | Party |
|---|---|---|---|---|
| https://metrics.cedrc.cnr.it/matomo.js | 63 KB | 37 KB (60%) | ✓ | 3rd |
| https://www.cnr.it/sites/all/themes/custom/cnr03_theme/bootstrap/js/popover.js?tdslzg | 2 KB | — | ✓ | 3rd |
| https://www.cnr.it/sites/all/libraries/mediaboxes/plugins/js/modernizr.custom.min.js?tdslzg | 1 KB | — | ✓ | 3rd |
| https://www.cnr.it/misc/jquery.once.js?v=1.2 | 2 KB | — | ✓ | 3rd |
| https://www.cnr.it/misc/drupal.js?tdslzg | 7 KB | — | ✗ | 3rd |
| https://www.cnr.it/sites/all/themes/custom/cnr03_theme/bootstrap/js/scrollspy.js?tdslzg | 2 KB | — | ✓ | 3rd |
| https://www.cnr.it/sites/all/themes/custom/cnr03_theme/bootstrap/js/affix.js?tdslzg | 2 KB | — | ✓ | 3rd |
| https://www.cnr.it/sites/all/themes/custom/cnr03_theme/bootstrap/js/alert.js?tdslzg | 1 KB | — | ✓ | 3rd |
| https://www.cnr.it/sites/all/themes/custom/cnr03_theme/bootstrap/js/button.js?tdslzg | 2 KB | — | ✓ | 3rd |
| https://www.cnr.it/sites/all/themes/custom/cnr03_theme/bootstrap/js/carousel.js?tdslzg | 2 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
A+Resource CachingAll resources properly cachedPASS
A+Critical Rendering PathNo render-blocking resourcesPASS
A+Resource HintsNo optimization neededPASS
Network Waterfall63 requests over 1335msINFO
Third-Party Script CostPer-script blocking time, transfer cost, and cache headersINFO
| Script | Category | Execution | Transfer | Unused | Monthly Cost | Verdict |
|---|---|---|---|---|---|---|
www.cnr.it www.cnr.it | Other | 114ms | 13 KB | — | €1/mo | Optional |
Unattributable Unattributable | Other | 91ms | 0 KB | — | €1/mo | Optional |
www.cnr.it www.cnr.it | Other | 81ms | 32 KB | — | €1/mo | Optional |
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