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Performance

· 14 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.
SCORE
73
GRADE
C
FIX
4
REVIEW
2
PASS
6
INFO
2

Performance-focused optimization plan with CWV assessment, top offenders, and time estimates

Mobile Desktop
23
Performance Overall performance score (0–100) based on Core Web Vitals and other metrics. 90+ is good.
94
Accessibility Measures how accessible the page is for users with disabilities. Checks color contrast, ARIA labels, and semantic HTML.
77
Best Practices Checks for modern web development best practices including HTTPS, no console errors, and secure JavaScript.
83
SEO Measures basic SEO optimizations: meta tags, crawlability, link text, and mobile friendliness.

First Contentful Paint First Contentful Paint — how long until the browser renders the first piece of content. Under 1.8s is good.

8.42 s

Largest Contentful Paint Largest Contentful Paint — how long until the largest visible element loads. Under 2.5s is good.

17.63 s

Total Blocking Time Total Blocking Time — total time the main thread was blocked, preventing user input. Under 200ms is good.

7.06 s

Cumulative Layout Shift Cumulative Layout Shift — measures visual stability. How much the page layout shifts during loading. Under 0.1 is good.

0.107

Speed Index Speed Index — how quickly content is visually displayed during load. Under 3.4s is good.

10.21 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.

22.19 s

Page Load Progression

664 ms
1.3 s
2.0 s
2.7 s
3.3 s
4.0 s
4.6 s
5.3 s
Checks
14
6 PASS 2 REVIEW 4 FIX
F
Page Weight Budget
Action
3.2 MB transferred, 170 requests
FIX
3.2 MB transferred, 170 requests
Warning::
Page weighs 14.5 MB (3.2 MB transferred)
Warning::
JavaScript is 1.8 MB — consider code splitting or lazy loading
Large JavaScript bundles delay interactivity. Split code by route or defer non-critical scripts.
Got: 1.8 MB
Warning::
170 HTTP requests — consider bundling or reducing
Each request adds latency. Bundle small files, use sprites, or eliminate unnecessary requests.
Info::
Estimated 0.67 g CO2 per page load
3.2 MB / 2.4 MB budget
3.2 MB transferred
170 requests
0.67 g CO2 per page load
JavaScript 1.8 MiB 58%
Images 899.9 KiB 28%
Other 243.2 KiB 7%
Fonts 64.9 KiB 2%
CSS 64.0 KiB 2%
Other 50.9 KiB 2%
Other 24.0 KiB 1%
HTML 14.4 KiB 0%
Other 0 B 0%
0 2.4 MB 4.9 MB
Over budget

Large JavaScript bundles delay interactivity. Split code by route or defer non-critical scripts.

Why this matters

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.

Why this matters

High HTTP request count — bundling, sprite-ing, and HTTP/2 server push can reduce per-request overhead.

Source: web.dev

F
JS Execution Cost
Action
23588ms total JS execution
FIX
23588ms total JS execution
Warning::
https://www.delta.com/resources/df032bb95163120c0d...: 4662ms CPU time
Warning::
https://www.delta.com/homepage/26.3.8/mach-core/br...: 4221ms CPU time
Warning::
Unattributable: 3483ms CPU time
Warning::
https://www.delta.com/NxvV2/ISv/V5F2/Si/veeSUD/1G7...: 2142ms CPU time
Warning::
https://www.delta.com/eu/en: 1932ms CPU time
Info::
Third-party scripts: 7411ms (31% of total)

Main Thread Breakdown

Script Evaluation 64% Other 17% Script Parsing & Compilation 10% Style & Layout 5%
ScriptTotalScriptingParse/CompileParty
https://www.delta.com/resources/df032bb95163120c0d0265eb98f27f913a30d77a1d98e4662ms4027ms142ms1st
https://www.delta.com/homepage/26.3.8/mach-core/browser/polyfills.js4221ms3408ms11ms1st
Unattributable3483ms868ms0ms3rd
https://www.delta.com/NxvV2/ISv/V5F2/Si/veeSUD/1G7hbLaQkOX7LS/fQUZPAE/fnJiRG/IXEUIB2142ms1908ms196ms1st
https://www.delta.com/eu/en1932ms76ms12ms1st
https://www.delta.com/NxvV2/ISv/V5F2/Si/veeSUD/wb7hbLaQ/K0ciPAE/UHQfJX/dcDxdt?v=807bcfdf-33b5-18b2-e4bf-1dd5341e02101612ms1315ms273ms1st
https://tms.delta.com/delta/dl_anderson/Bootstrap.js1340ms1062ms210ms3rd
https://assets.adobedtm.com/3b29aa0834b1/0e49b4a4297a/launch-ab7c06f028a9.min.js917ms671ms229ms3rd
https://www.delta.com/homepage/26.3.8/mach-core/browser/main.js834ms18ms800ms1st
https://cdn.cookielaw.org/scripttemplates/202503.1.0/otBannerSdk.js601ms423ms86ms3rd

Showing top 10 of 24 scripts

F
JS Bundles
Action
57 scripts, 1.2 MB unused
FIX
57 scripts, 1.2 MB unused
Warning::
https://www.delta.com/homepage/26.3.8/mach-core/br...: 348 KB unused (53%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://www.delta.com/homepage/26.3.8/mach-core/br...: 348 KB unused (53%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://cdn.cookielaw.org/scripttemplates/202503.1...: 62 KB unused (53%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://tms.delta.com/delta/dl_anderson/Bootstrap....: 45 KB unused (47%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://tms.delta.com/delta/dl_anderson/Bootstrap....: 45 KB unused (47%)
Consider code splitting or tree shaking to reduce unused code.
Info::
Total unused JavaScript: 1.2 MB
1183 KB unused JavaScript

Downloaded but never executed on this page.

ScriptSizeUnusedMinifiedParty
https://www.delta.com/homepage/26.3.8/mach-core/browser/main.js0 KB348 KB (53%)✓1st
https://www.delta.com/homepage/26.3.8/mach-core/browser/main.js662 KB348 KB (53%)✓1st
https://cdn.cookielaw.org/scripttemplates/202503.1.0/otBannerSdk.js116 KB62 KB (53%)✓3rd
https://tms.delta.com/delta/dl_anderson/Bootstrap.js96 KB45 KB (47%)✓3rd
https://tms.delta.com/delta/dl_anderson/Bootstrap.js0 KB45 KB (47%)✓3rd
https://assets.adobedtm.com/3b29aa0834b1/0e49b4a4297a/launch-ab7c06f028a9.min.js100 KB37 KB (37%)✓3rd
https://assets.adobedtm.com/3b29aa0834b1/0e49b4a4297a/launch-ab7c06f028a9.min.js0 KB37 KB (37%)✓3rd
https://www.delta.com/NxvV2/ISv/V5F2/Si/veeSUD/1G7hbLaQkOX7LS/fQUZPAE/fnJiRG/IXEUIB173 KB36 KB (21%)✓1st
https://www.delta.com/NxvV2/ISv/V5F2/Si/veeSUD/1G7hbLaQkOX7LS/fQUZPAE/fnJiRG/IXEUIB173 KB36 KB (21%)✓1st
https://www.delta.com/NxvV2/ISv/V5F2/Si/veeSUD/wb7hbLaQ/K0ciPAE/UHQfJX/dcDxdt?v=807bcfdf-33b5-18b2-e4bf-1dd5341e02100 KB33 KB (21%)✓1st

Consider code splitting or tree shaking to reduce unused code.

Why this matters

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.

Why this matters

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.

Why this matters

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.

Why this matters

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.

Why this matters

This bundle has high unused code — code-split or tree-shake to ship only what executes.

Source: web.dev / Lighthouse coverage

D
HTTP Caching
Action
No cache headers
FIX
No cache headers
Warning::
No Cache-Control header found
Browsers will use heuristic caching, which can be unpredictable. Set explicit cache headers.
Info::
ETag present — enables conditional (304) responses
Info::
Last-Modified header present

No Cache-Control header

Adding a Cache-Control header can significantly improve repeat-visit performance.

B
Image Optimization
42 images, 0 KB saveable
REVIEW
42 images, 0 KB saveable
Info::
All images are well-optimized
42 images 897 KB
0 oversized -0 KB
19 legacy format
0 missing dimensions CLS risk
C
Green Hosting
Action
Whether the site is served from green-energy infrastructure
REVIEW

Green Hosting

No green hosting detected

A+
Third-Party Impact
18% third-party, 0 ms blocking
PASS
18% third-party, 0 ms blocking
Info::
Third-party code accounts for 18% of page weight (590.0 KiB of 3.2 MiB)
Info::
Third-party blocking time is low (0 ms)
82%
18%
First-party Third-party
A+
Text Compression
All text resources are compressed
PASS
All text resources are compressed
Info::
All text resources are compressed
All text resources are properly compressed.
A+
Font Loading
10 fonts (65 KB)
PASS
10 fonts (65 KB)
Info::
10 font(s) use font-display: swap (FOUT risk but functional)

Web fonts

10

65 KB total

Render-blocking

0

of 10

Dominant font-display

swap

Most common across fonts

Font loading timeline
Transfer FOIT (block) FOUT (swap)
0 ms 2.0 s 4.0 s 6.0 s 8.0 s 10.0 s 12.0 s 14.0 s 16.0 s 18.0 s FCP 8.4 s LCP 17.6 shttps://www.delta.com/content/dam/delta-applications/mach-1/assets/fonts/CB8837CA379681FED.woff2CB8837CA379681FED.woff2 https://www.delta.com/content/dam/delta-applications/mach-1/assets/fonts/CB8837CA379681FED.woff2 — 13.0 KiB — 0 ms — font-display: swaphttps://www.delta.com/content/dam/delta-applications/mach-1/assets/fonts/AABA9C13AF9C5C638.woff2AABA9C13AF9C5C638.woff2 https://www.delta.com/content/dam/delta-applications/mach-1/assets/fonts/AABA9C13AF9C5C638.woff2 — 12.8 KiB — 0 ms — font-display: swaphttps://www.delta.com/content/dam/delta-applications/mach-1/assets/fonts/3955045D2CF71A4B6.woff23955045D2CF71A4B6.woff2 https://www.delta.com/content/dam/delta-applications/mach-1/assets/fonts/3955045D2CF71A4B6.woff2 — 13.0 KiB — 0 ms — font-display: swaphttps://www.delta.com/content/dam/delta-applications/mach-1/assets/fonts/whitney-condensed.woff2whitney-condensed.woff2 https://www.delta.com/content/dam/delta-applications/mach-1/assets/fonts/whitney-condensed.woff2 — 13.3 KiB — 0 ms — font-display: swaphttps://www.delta.com/content/dam/delta-applications/mach-1/assets/fonts/A32A3E152E391B379.woff2A32A3E152E391B379.woff2 https://www.delta.com/content/dam/delta-applications/mach-1/assets/fonts/A32A3E152E391B379.woff2 — 0 B — 0 ms — font-display: swaphttps://www.delta.com/content/dam/delta-applications/mach-1/assets/fonts/CB8837CA379681FED.woff2CB8837CA379681FED.woff2 https://www.delta.com/content/dam/delta-applications/mach-1/assets/fonts/CB8837CA379681FED.woff2 — 0 B — 0 ms — font-display: swaphttps://www.delta.com/content/dam/delta-applications/mach-1/assets/fonts/AABA9C13AF9C5C638.woff2AABA9C13AF9C5C638.woff2 https://www.delta.com/content/dam/delta-applications/mach-1/assets/fonts/AABA9C13AF9C5C638.woff2 — 0 B — 0 ms — font-display: swaphttps://www.delta.com/content/dam/delta-applications/mach-1/assets/fonts/3955045D2CF71A4B6.woff23955045D2CF71A4B6.woff2 https://www.delta.com/content/dam/delta-applications/mach-1/assets/fonts/3955045D2CF71A4B6.woff2 — 0 B — 0 ms — font-display: swaphttps://www.delta.com/content/dam/delta-applications/mach-1/assets/fonts/whitney-condensed.woff2whitney-condensed.woff2 https://www.delta.com/content/dam/delta-applications/mach-1/assets/fonts/whitney-condensed.woff2 — 0 B — 0 ms — font-display: swaphttps://www.delta.com/content/dam/delta-applications/mach-1/assets/fonts/A32A3E152E391B379.woff2A32A3E152E391B379.woff2 https://www.delta.com/content/dam/delta-applications/mach-1/assets/fonts/A32A3E152E391B379.woff2 — 12.8 KiB — 0 ms — font-display: swap
CB8837CA379681FED.woff2 woff2 swap
Size 13 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
AABA9C13AF9C5C638.woff2 woff2 swap
Size 13 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
3955045D2CF71A4B6.woff2 woff2 swap
Size 13 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
whitney-condensed.woff2 woff2 swap
Size 13 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
A32A3E152E391B379.woff2 woff2 swap
Size 0 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
CB8837CA379681FED.woff2 woff2 swap
Size 0 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
AABA9C13AF9C5C638.woff2 woff2 swap
Size 0 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
3955045D2CF71A4B6.woff2 woff2 swap
Size 0 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
whitney-condensed.woff2 woff2 swap
Size 0 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
A32A3E152E391B379.woff2 woff2 swap
Size 13 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
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 Caching
All resources properly cached
PASS
All resources properly cached
Info::
No caching issues found
All static resources have appropriate caching headers.
A+
Critical Rendering Path
No render-blocking resources
PASS
No render-blocking resources
Info::
No render-blocking resources detected
A+
Resource Hints
No optimization needed
PASS
No optimization needed
Info::
No resource hint issues
Network Waterfall
170 requests over 0ms
INFO

Performance analysis not available for this result.

Third-Party Script Cost
Per-script blocking time, transfer cost, and cache headers
INFO
31% of JavaScript execution is third-party
First-party Third-party 7411ms · 151KB · $98/mo
Unattributable
Other
Costly
Execution 3483ms
Transfer 0 KB
Monthly Cost $46/mo
tms.delta.com
Other
Costly
Execution 1340ms
Transfer 0 KB
Unused 47%
Monthly Cost $18/mo
assets.adobedtm.com
Other
Costly
Execution 917ms
Transfer 0 KB
Unused 37%
Monthly Cost $12/mo
OneTrust
Consent
Essential
Execution 601ms
Transfer 116 KB
Unused 53%
Monthly Cost $8/mo
s.go-mpulse.net
Other
Costly
Execution 244ms
Transfer 0 KB
Unused 61%
Monthly Cost $3/mo
p11.techlab-cdn.com
Other
Optional
Execution 156ms
Transfer 0 KB
Monthly Cost $2/mo
p11.techlab-cdn.com
Other
Optional
Execution 139ms
Transfer 0 KB
Monthly Cost $2/mo
tms.delta.com
Other
Optional
Execution 91ms
Transfer 1 KB
Monthly Cost $1/mo
assets.adobedtm.com
Other
Optional
Execution 90ms
Transfer 0 KB
Monthly Cost $1/mo
tms.delta.com
Other
Optional
Execution 86ms
Transfer 12 KB
Monthly Cost $1/mo
tms.delta.com
Other
Optional
Execution 71ms
Transfer 19 KB
Monthly Cost $1/mo
assets.adobedtm.com
Other
Optional
Execution 70ms
Transfer 2 KB
Monthly Cost $1/mo
assets.adobedtm.com
Other
Optional
Execution 68ms
Transfer 1 KB
Monthly Cost $1/mo
OneTrust
Consent
Essential
Execution 55ms
Transfer 0 KB
Monthly Cost $1/mo

These scripts may cost more than they're worth

  • Unattributable adds 3483ms and costs ~$46/month
  • tms.delta.com adds 1340ms and costs ~$18/month
  • assets.adobedtm.com adds 917ms and costs ~$12/month
  • s.go-mpulse.net adds 244ms and costs ~$3/month

Unattributable takes 3483ms of CPU time. Consider loading it asynchronously or replacing it with a lighter alternative.

Why this matters

This script has high main-thread execution time — optimize hot paths or defer.

Source: web.dev

tms.delta.com takes 1340ms of CPU time. Consider loading it asynchronously or replacing it with a lighter alternative.

Why this matters

This script has high main-thread execution time — optimize hot paths or defer.

Source: web.dev

assets.adobedtm.com takes 917ms of CPU time. Consider loading it asynchronously or replacing it with a lighter alternative.

Why this matters

This script has high main-thread execution time — optimize hot paths or defer.

Source: web.dev

53% of OneTrust's code is unused. The script may be loading features you don't use.

Why this matters

Bundle has high unused-code ratio — tree-shaking and route-splitting recover the wasted bytes.

Source: web.dev

s.go-mpulse.net takes 244ms of CPU time. Consider loading it asynchronously or replacing it with a lighter alternative.

Why this matters

This script has high main-thread execution time — optimize hot paths or defer.

Source: web.dev

61% of s.go-mpulse.net's code is unused. The script may be loading features you don't use.

Why this matters

Bundle has high unused-code ratio — tree-shaking and route-splitting recover the wasted bytes.

Source: web.dev

How third-party costs are calculated

All checks on this page are automated. Results are estimates - run targeted manual reviews when the score affects a release decision.

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