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.
1.05 s
Largest Contentful Paint Largest Contentful Paint — how long until the largest visible element loads. Under 2.5s is good.
1.70 s
Total Blocking Time Total Blocking Time — total time the main thread was blocked, preventing user input. Under 200ms is good.
462 ms
Cumulative Layout Shift Cumulative Layout Shift — measures visual stability. How much the page layout shifts during loading. Under 0.1 is good.
0.004
Speed Index Speed Index — how quickly content is visually displayed during load. Under 3.4s is good.
2.49 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.
5.81 s
Page Load Progression
FPage Weight BudgetAction3.8 MB transferred, 104 requestsFIX
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
Subset fonts to include only used characters, or switch to system font stacks.
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.
High HTTP request count — bundling, sprite-ing, and HTTP/2 server push can reduce per-request overhead.
Source: web.dev
DThird-Party ImpactAction100% third-party, 0 ms blockingFIX
DJS Execution CostAction2912ms total JS executionFIX
Main Thread Breakdown
| Script | Total | Scripting | Parse/Compile | Party |
|---|---|---|---|---|
| https://www.eldiario.es/ | 591ms | 68ms | 6ms | 3rd |
| Unattributable | 440ms | 109ms | 0ms | 3rd |
| https://www.googletagmanager.com/gtm.js?id=GTM-WRDHMPW | 344ms | 278ms | 55ms | 3rd |
| https://pagead2.googlesyndication.com/pagead/managed/js/gpt/m202604200101/pubads_impl.js?cb=31097964 | 204ms | 133ms | 25ms | 3rd |
| https://sdk.privacy-center.org/sdk/22ecd6bfac93de604efec0b75b2c796ee1675f92/modern/ui-web-en-web.22ecd6bfac93de604efec0b75b2c796ee1675f92.js | 198ms | 123ms | 10ms | 3rd |
| https://www.eldiario.es/app.h-5bd2772bdef2d90ace0e.js | 198ms | 141ms | 5ms | 3rd |
| https://marfeelexperimentsexperienceengine.mrf.io/experimentsexperience/render?id=AC_4Ph4IkFsQZ2_bECPMYqc-Q&experimentType=HeadlineAB&version=esnext | 189ms | 180ms | 0ms | 3rd |
| https://www.eldiario.es/edi-app.h-5bd2772bdef2d90ace0e.js | 106ms | 94ms | 10ms | 3rd |
| https://static.eldiario.es/statics/public/sibbo/prebid_eldiario_es_20260317.min.js | 104ms | 83ms | 20ms | 3rd |
| https://www.eldiario.es/vendor.h-5bd2772bdef2d90ace0e.js | 95ms | 7ms | 86ms | 3rd |
Showing top 10 of 16 scripts
FJS BundlesAction42 scripts, 1.1 MB unusedFIX
Downloaded but never executed on this page.
| Script | Size | Unused | Minified | Party |
|---|---|---|---|---|
| https://www.eldiario.es/vendor.h-5bd2772bdef2d90ace0e.js | 474 KB | 429 KB (91%) | ✓ | 3rd |
| https://pagead2.googlesyndication.com/pagead/managed/js/gpt/m202604200101/pubads_impl.js?cb=31097964 | 188 KB | 132 KB (70%) | ✓ | 3rd |
| https://static.eldiario.es/statics/public/sibbo/prebid_eldiario_es_20260317.min.js | 149 KB | 105 KB (71%) | ✓ | 3rd |
| https://accounts.google.com/gsi/client | 96 KB | 71 KB (75%) | ✓ | 3rd |
| https://www.googletagmanager.com/gtag/js?id=G-4RZPWREGF3&cx=c>m=4e64h1 | 174 KB | 67 KB (39%) | ✓ | 3rd |
| https://c.amazon-adsystem.com/aax2/apstag.js | 91 KB | 50 KB (55%) | ✓ | 3rd |
| https://www.googletagmanager.com/gtm.js?id=GTM-WRDHMPW | 181 KB | 49 KB (27%) | ✓ | 3rd |
| https://cdn.onesignal.com/sdks/OneSignalPageSDKES6.js?v=151607 | 69 KB | 48 KB (71%) | ✓ | 3rd |
| https://news.google.com/swg/js/v1/swg.js | 71 KB | 47 KB (68%) | ✓ | 3rd |
| https://ats-wrapper.privacymanager.io/ats-modules/96382f5c-08c1-4862-a8c6-aadb581efa79/ats.js | 75 KB | 41 KB (55%) | ✓ | 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
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
FPage Weight InventoryAction104 resources · 3.8 MB · 1.1 MB savings availableFIX
~1.1 MiB of savings available
| # | Resource | Type | Size | Cache | Unused | 3rd party | Issues |
|---|---|---|---|---|---|---|---|
| — | — | ||||||
| 104 resources | 3.8 MiB | ||||||
FHTTP CachingActionNo cache headersFIX
No Cache-Control header
Adding a Cache-Control header can significantly improve repeat-visit performance.
BImage Optimization28 images, 0 KB saveableREVIEW
CGreen HostingActionWhether the site is served from green-energy infrastructureREVIEW
Green Hosting
No green hosting detected
A+Text CompressionAll text resources are compressedPASS
A+Font Loading11 fonts (642 KB)PASS
Web fonts
11
642 KB total
Render-blocking
0
of 11
Dominant font-display
swap
Most common across fonts
Font loading timeline
- Convert to woff2 for ~30% smaller file size
- Subset this font — over 100 KB suggests Latin Extended or full glyph coverage that most pages don't need
- 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 ~128 KB and ~256 ms
A+Resource CachingAll resources properly cachedPASS
A+Critical Rendering PathNo render-blocking resourcesPASS
A+Resource HintsNo optimization neededPASS
Network Waterfall104 requests over 3868msINFO
Third-Party Script CostPer-script blocking time, transfer cost, and cache headersINFO
| Script | Category | Execution | Transfer | Unused | Monthly Cost | Verdict |
|---|---|---|---|---|---|---|
www.eldiario.es www.eldiario.es | Other | 591ms | 95 KB | — | €3/mo | Costly |
Unattributable Unattributable | Other | 440ms | 0 KB | — | €2/mo | Costly |
Google Tag Manager www.googletagmanager.com | Tag Manager | 344ms | 181 KB | 27% | €2/mo | Costly |
pagead2.googlesyndication.com pagead2.googlesyndication.com | Other | 204ms | 188 KB | 70% | €1/mo | Costly |
sdk.privacy-center.org sdk.privacy-center.org | Other | 198ms | 54 KB | — | €1/mo | Optional |
www.eldiario.es www.eldiario.es | Other | 198ms | 26 KB | — | €1/mo | Optional |
marfeelexperimentsexperienceengine.mrf.io marfeelexperimentsexperienceengine.mrf.io | Other | 189ms | 9 KB | — | €1/mo | Optional |
www.eldiario.es www.eldiario.es | Other | 106ms | 33 KB | 76% | €1/mo | Optional |
static.eldiario.es static.eldiario.es | Other | 104ms | 149 KB | 71% | €1/mo | Optional |
www.eldiario.es www.eldiario.es | Other | 95ms | 474 KB | 91% | €0/mo | Optional |
sdk.privacy-center.org sdk.privacy-center.org | Other | 94ms | 101 KB | 45% | €0/mo | Optional |
Google Tag Manager www.googletagmanager.com | Tag Manager | 90ms | 174 KB | 39% | €0/mo | Optional |
c.amazon-adsystem.com c.amazon-adsystem.com | Other | 75ms | 91 KB | 55% | €0/mo | Optional |
Facebook Pixel connect.facebook.net | Advertising | 67ms | 40 KB | — | €0/mo | Optional |
cdn.taboola.com cdn.taboola.com | Other | 65ms | 27 KB | — | €0/mo | Optional |
Facebook Pixel connect.facebook.net | Advertising | 52ms | 97 KB | 36% | €0/mo | Optional |
These scripts may cost more than they're worth
- www.eldiario.es adds 591ms and costs ~€3/month
- Unattributable adds 440ms and costs ~€2/month
- Google Tag Manager adds 344ms and costs ~€2/month
- pagead2.googlesyndication.com adds 204ms and costs ~€1/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.eldiario.es takes 591ms 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 440ms 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
Google Tag Manager takes 344ms 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
pagead2.googlesyndication.com takes 204ms 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
70% of pagead2.googlesyndication.com's code is unused. The script may be loading features you don't use.
Bundle has high unused-code ratio — tree-shaking and route-splitting recover the wasted bytes.
Source: web.dev
76% of www.eldiario.es's code is unused. The script may be loading features you don't use.
Bundle has high unused-code ratio — tree-shaking and route-splitting recover the wasted bytes.
Source: web.dev
71% of static.eldiario.es's code is unused. The script may be loading features you don't use.
Bundle has high unused-code ratio — tree-shaking and route-splitting recover the wasted bytes.
Source: web.dev
91% of www.eldiario.es's code is unused. The script may be loading features you don't use.
Bundle has high unused-code ratio — tree-shaking and route-splitting recover the wasted bytes.
Source: web.dev
55% of c.amazon-adsystem.com's code is unused. The script may be loading features you don't use.
Bundle has high unused-code ratio — tree-shaking and route-splitting recover the wasted bytes.
Source: web.dev