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.
987 ms
Largest Contentful Paint Largest Contentful Paint — how long until the largest visible element loads. Under 2.5s is good.
1.93 s
Total Blocking Time Total Blocking Time — total time the main thread was blocked, preventing user input. Under 200ms is good.
155 ms
Cumulative Layout Shift Cumulative Layout Shift — measures visual stability. How much the page layout shifts during loading. Under 0.1 is good.
0.008
Speed Index Speed Index — how quickly content is visually displayed during load. Under 3.4s is good.
1.41 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.
3.87 s
Page Load Progression
DPage Weight BudgetAction2.4 MB transferred, 132 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
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 BundlesAction52 scripts, 794 KB unusedFIX
Downloaded but never executed on this page.
| Script | Size | Unused | Minified | Party |
|---|---|---|---|---|
| https://cdn.images.express.co.uk/js/dist/prebid20260414.min.js | 174 KB | 142 KB (81%) | ✓ | 3rd |
| https://securepubads.g.doubleclick.net/pagead/managed/js/gpt/m202604100101/pubads_impl.js | 186 KB | 121 KB (65%) | ✓ | 3rd |
| https://cdn.images.express.co.uk/@trinitymirrordigital/auth-ui/auth-ui.min.js?v=1fd39c450ef4387c0718b2aa4d9d179fde134e19 | 131 KB | 89 KB (68%) | ✓ | 3rd |
| https://premium.express.co.uk/js/dist/app202602174.min.js | 97 KB | 66 KB (68%) | ✓ | 3rd |
| https://cdn.amplitude.com/libs/analytics-browser-gtm-wrapper-3.18.1.js.br | 74 KB | 63 KB (85%) | ✓ | 3rd |
| https://premium.express.co.uk/js/dist/app-pp20260212.min.js | 91 KB | 58 KB (64%) | ✓ | 3rd |
| https://www.googletagmanager.com/gtm.js?id=GTM-NX7XL77 | 170 KB | 56 KB (33%) | ✓ | 3rd |
| https://www.googletagmanager.com/gtag/js?id=AW-17949595080&cx=c>m=4e64e1 | 140 KB | 54 KB (39%) | ✓ | 3rd |
| https://connect.facebook.net/en_US/fbevents.js | 96 KB | 34 KB (35%) | ✓ | 3rd |
| https://cdn.images.express.co.uk/js/dist/prebid_express20260414.min.js | 81 KB | 34 KB (42%) | ✓ | 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 InventoryAction132 resources · 2.4 MB · 794 KB savings availableFIX
~793.9 KiB of savings available
| # | Resource | Type | Size | Cache | Unused | 3rd party | Issues |
|---|---|---|---|---|---|---|---|
| — | — | ||||||
| 132 resources | 2.4 MiB | ||||||
CImage OptimizationAction42 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
CJS Execution CostAction1611ms total JS executionREVIEW
Main Thread Breakdown
| Script | Total | Scripting | Parse/Compile | Party |
|---|---|---|---|---|
| https://www.express.co.uk/ | 556ms | 89ms | 12ms | 3rd |
| Unattributable | 253ms | 9ms | 0ms | 3rd |
| https://www.googletagmanager.com/gtm.js?id=GTM-NX7XL77 | 221ms | 183ms | 19ms | 3rd |
| https://securepubads.g.doubleclick.net/pagead/managed/js/gpt/m202604100101/pubads_impl.js | 134ms | 116ms | 17ms | 3rd |
| https://cmp.inmobi.com/tcfv2/61/cmp2.js?referer=www.express.co.uk | 108ms | 75ms | 17ms | 3rd |
| https://www.googletagmanager.com/gtag/js?id=AW-17949595080&cx=c>m=4e64e1 | 85ms | 72ms | 11ms | 3rd |
| https://cdn.images.express.co.uk/js/dist/prebid_express20260414.min.js | 80ms | 64ms | 13ms | 3rd |
| https://cdn.images.express.co.uk/js/dist/prebid20260414.min.js | 68ms | 48ms | 19ms | 3rd |
| https://cdn.images.express.co.uk/@trinitymirrordigital/auth-ui/auth-ui.min.js?v=1fd39c450ef4387c0718b2aa4d9d179fde134e19 | 55ms | 38ms | 17ms | 3rd |
| https://connect.facebook.net/en_US/fbevents.js | 52ms | 41ms | 11ms | 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 Loading1 fonts (19 KB)PASS
Web fonts
1
19 KB total
Render-blocking
0
of 1
Dominant font-display
swap
Most common across fonts
Font loading timeline
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)
A+Resource CachingAll resources properly cachedPASS
A+Critical Rendering PathNo render-blocking resourcesPASS
A+Resource HintsNo optimization neededPASS
AHTTP Cachingmax-age=180 (3 minutes)PASS
public,max-age=180
| Directive | Value | Meaning |
|---|---|---|
| public | — | Any cache may store this response |
| max-age | 180 | Cache for 3 minutes |
Network Waterfall132 requests over 5998msINFO
Third-Party Script CostPer-script blocking time, transfer cost, and cache headersINFO
| Script | Category | Execution | Transfer | Unused | Monthly Cost | Verdict |
|---|---|---|---|---|---|---|
www.express.co.uk www.express.co.uk | Other | 556ms | 100 KB | — | £6/mo | Costly |
Unattributable Unattributable | Other | 253ms | 0 KB | — | £3/mo | Costly |
Google Tag Manager www.googletagmanager.com | Tag Manager | 221ms | 170 KB | 33% | £2/mo | Costly |
securepubads.g.doubleclick.net securepubads.g.doubleclick.net | Other | 134ms | 186 KB | 65% | £1/mo | Optional |
cmp.inmobi.com cmp.inmobi.com | Other | 108ms | 117 KB | — | £1/mo | Optional |
Google Tag Manager www.googletagmanager.com | Tag Manager | 85ms | 140 KB | 39% | £1/mo | Optional |
cdn.images.express.co.uk cdn.images.express.co.uk | Other | 80ms | 81 KB | 42% | £1/mo | Optional |
cdn.images.express.co.uk cdn.images.express.co.uk | Other | 68ms | 174 KB | 81% | £1/mo | Optional |
cdn.images.express.co.uk cdn.images.express.co.uk | Other | 55ms | 131 KB | 68% | £1/mo | Optional |
Facebook Pixel connect.facebook.net | Advertising | 52ms | 96 KB | 35% | £1/mo | Optional |
These scripts may cost more than they're worth
- www.express.co.uk adds 556ms and costs ~£6/month
- Unattributable adds 253ms and costs ~£3/month
- Google Tag Manager adds 221ms and costs ~£2/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.express.co.uk takes 556ms 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 253ms 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 221ms 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
65% 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
81% of cdn.images.express.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
68% of cdn.images.express.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