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.
949 ms
Largest Contentful Paint Largest Contentful Paint — how long until the largest visible element loads. Under 2.5s is good.
2.02 s
Total Blocking Time Total Blocking Time — total time the main thread was blocked, preventing user input. Under 200ms is good.
30 ms
Cumulative Layout Shift Cumulative Layout Shift — measures visual stability. How much the page layout shifts during loading. Under 0.1 is good.
0.000
Speed Index Speed Index — how quickly content is visually displayed during load. Under 3.4s is good.
2.55 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.
5.21 s
Page Load Progression
819 ms
1.6 s
2.5 s
3.3 s
4.1 s 4.9 s
5.7 s
6.6 sFPage Weight BudgetAction5.0 MB transferred, 216 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
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
FJS BundlesAction65 scripts, 705 KB unusedFIX
Downloaded but never executed on this page.
| Script | Size | Unused | Minified | Party |
|---|---|---|---|---|
| https://securepubads.g.doubleclick.net/pagead/managed/js/gpt/m202604160201/pubads_impl.js | 188 KB | 140 KB (75%) | ✓ | 3rd |
| https://s2-prod.walesonline.co.uk/@trinitymirrordigital/auth-ui/auth-ui.min.js?v=v260318 | 133 KB | 79 KB (60%) | ✓ | 3rd |
| https://www.googletagmanager.com/gtm.js?id=GTM-WL2JKZG | 168 KB | 71 KB (42%) | ✓ | 3rd |
| https://cmp.inmobi.com/tcfv2/61/cmp2.js?referer=walesonline.co.uk | 134 KB | 69 KB (52%) | ✓ | 3rd |
| https://cdn.amplitude.com/libs/analytics-browser-gtm-wrapper-2.36.8.min.js.br | 80 KB | 66 KB (84%) | ✓ | 3rd |
| https://cmp.inmobi.com/tcfv2/61/cmp2ui-en.js | 125 KB | 60 KB (48%) | ✓ | 3rd |
| https://www.walesonline.co.uk/nav-web-static/main-7d527e9aab619128ce0f0a829af162c8310e6e1a/_next/static/chunks/9308-a0fa6767bee242d9.js | 81 KB | 36 KB (46%) | ✓ | 3rd |
| https://cdn.onesignal.com/sdks/web/v16/OneSignalSDK.page.es6.js?v=160603 | 42 KB | 32 KB (78%) | ✓ | 3rd |
| https://cdn.eu.amplitude.com/libs/analytics-browser-2.25.0-min.js.gz | 50 KB | 32 KB (64%) | ✓ | 3rd |
| https://cdn.amplitude.com/libs/analytics-browser-gtm-2.36.8-min.js.gz | 55 KB | 28 KB (52%) | ✓ | 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 InventoryAction216 resources · 5.0 MB · 705 KB savings availableFIX
~705.1 KiB of savings available
| # | Resource | Type | Size | Cache | Unused | 3rd party | Issues |
|---|---|---|---|---|---|---|---|
| — | — | ||||||
| 216 resources | 5.0 MiB | ||||||
FHTTP CachingActionNo cache headersFIX
No Cache-Control header
Adding a Cache-Control header can significantly improve repeat-visit performance.
CImage OptimizationAction75 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
CJS Execution CostAction1798ms total JS executionREVIEW
Main Thread Breakdown
| Script | Total | Scripting | Parse/Compile | Party |
|---|---|---|---|---|
| https://www.walesonline.co.uk/ | 750ms | 6ms | 22ms | 3rd |
| Unattributable | 283ms | 17ms | 0ms | 3rd |
| https://www.walesonline.co.uk/nav-web-static/main-7d527e9aab619128ce0f0a829af162c8310e6e1a/_next/static/chunks/3794-7315db15a5700b37.js | 258ms | 240ms | 5ms | 3rd |
| https://cmp.inmobi.com/tcfv2/61/cmp2ui-en.js | 123ms | 72ms | 10ms | 3rd |
| https://cmp.inmobi.com/tcfv2/61/cmp2.js?referer=walesonline.co.uk | 119ms | 95ms | 10ms | 3rd |
| https://www.googletagmanager.com/gtm.js?id=GTM-WL2JKZG | 86ms | 68ms | 15ms | 3rd |
| https://scripts.webcontentassessor.com/scripts/370edbafa5296ef2074359ed0f0cb50d2775bd2cd6067dc81a99998410a888b3 | 61ms | 48ms | 13ms | 3rd |
| https://s2-prod.walesonline.co.uk/@trinitymirrordigital/auth-ui/auth-ui.min.js?v=v260318 | 60ms | 44ms | 12ms | 3rd |
| https://securepubads.g.doubleclick.net/pagead/managed/js/gpt/m202604160201/pubads_impl.js | 58ms | 38ms | 16ms | 3rd |
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 Loading18 fonts (526 KB)PASS
Web fonts
18
526 KB total
Render-blocking
0
of 18
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 ~27 KB and ~54 ms
A+Resource CachingAll resources properly cachedPASS
A+Critical Rendering PathNo render-blocking resourcesPASS
A+Resource HintsNo optimization neededPASS
Network Waterfall216 requests over 5380msINFO
Third-Party Script CostPer-script blocking time, transfer cost, and cache headersINFO
| Script | Category | Execution | Transfer | Unused | Monthly Cost | Verdict |
|---|---|---|---|---|---|---|
www.walesonline.co.uk www.walesonline.co.uk | Other | 750ms | 86 KB | — | £8/mo | Costly |
Unattributable Unattributable | Other | 283ms | 0 KB | — | £3/mo | Costly |
www.walesonline.co.uk www.walesonline.co.uk | Other | 258ms | 45 KB | 45% | £3/mo | Costly |
cmp.inmobi.com cmp.inmobi.com | Other | 123ms | 125 KB | 48% | £1/mo | Optional |
cmp.inmobi.com cmp.inmobi.com | Other | 119ms | 134 KB | 52% | £1/mo | Optional |
Google Tag Manager www.googletagmanager.com | Tag Manager | 86ms | 168 KB | 42% | £1/mo | Optional |
scripts.webcontentassessor.com scripts.webcontentassessor.com | Other | 61ms | 152 KB | — | £1/mo | Optional |
s2-prod.walesonline.co.uk s2-prod.walesonline.co.uk | Other | 60ms | 133 KB | 60% | £1/mo | Optional |
securepubads.g.doubleclick.net securepubads.g.doubleclick.net | Other | 58ms | 188 KB | 75% | £1/mo | Optional |
These scripts may cost more than they're worth
- www.walesonline.co.uk adds 750ms and costs ~£8/month
- Unattributable adds 283ms and costs ~£3/month
- www.walesonline.co.uk adds 258ms 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.walesonline.co.uk takes 750ms 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 283ms 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.walesonline.co.uk takes 258ms 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
52% of cmp.inmobi.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
60% of s2-prod.walesonline.co.uk'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
75% of securepubads.g.doubleclick.net'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