Performance
· 14 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.
945 ms
Largest Contentful Paint Largest Contentful Paint — how long until the largest visible element loads. Under 2.5s is good.
12.06 s
Total Blocking Time Total Blocking Time — total time the main thread was blocked, preventing user input. Under 200ms is good.
1.23 s
Cumulative Layout Shift Cumulative Layout Shift — measures visual stability. How much the page layout shifts during loading. Under 0.1 is good.
0.134
Speed Index Speed Index — how quickly content is visually displayed during load. Under 3.4s is good.
2.97 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.
12.08 s
Page Load Progression
FPage Weight BudgetAction21.3 MB transferred, 515 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
FJS Execution CostAction5032ms total JS executionFIX
Main Thread Breakdown
| Script | Total | Scripting | Parse/Compile | Party |
|---|---|---|---|---|
| https://www.lufthansa.com/etc/designs/dcep/clientlib-all/vite/js/2d7ed8d4.chunk.js | 1923ms | 1786ms | 2ms | 1st |
| https://www.lufthansa.com/digitalhangar/design-system/releases/v1.26.2/standalone/packages/maui-design-system.js | 1000ms | 820ms | 4ms | 1st |
| Unattributable | 887ms | 65ms | 0ms | 3rd |
| https://www.lufthansa.com/us/en/homepage | 523ms | 20ms | 4ms | 1st |
| https://www.lufthansa.com/etc/designs/dcep/clientlib-all/vite/js/63ac1397.chunk.js | 243ms | 17ms | 0ms | 1st |
| https://shop.lufthansa.com/booking/api/prefetch | 140ms | 117ms | 1ms | 3rd |
| https://www.lufthansa.com/etc/designs/dcep/clientlib-all/vite/js/app.07da5691.js | 89ms | 86ms | 0ms | 1st |
| https://www.lufthansa.com/etc.clientlibs/clientlibs/granite/jquery/granite.ed0d934d509c9dab702088c125c92b4f.js | 87ms | 83ms | 1ms | 1st |
| https://www.lufthansa.com/cdn-cgi/challenge-platform/scripts/jsd/main.js | 79ms | 76ms | 1ms | 1st |
| https://tags.tiqcdn.com/utag/lufthansa/main/prod/utag.js | 61ms | 36ms | 17ms | 3rd |
FJS BundlesAction400 scripts, 852 KB unusedFIX
Downloaded but never executed on this page.
| Script | Size | Unused | Minified | Party |
|---|---|---|---|---|
| https://www.lufthansa.com/etc/designs/dcep/clientlib-all/vite/js/2d7ed8d4.chunk.js | 345 KB | 167 KB (49%) | ✓ | 1st |
| https://www.lufthansa.com/etc/designs/dcep/clientlib-all/vite/js/cd23e20a.chunk.js | 167 KB | 150 KB (90%) | ✓ | 1st |
| https://www.lufthansa.com/etc/designs/dcep/clientlib-all/vite/js/d77d313a.chunk.js | 263 KB | 134 KB (51%) | ✓ | 1st |
| https://www.lufthansa.com/etc/designs/dcep/clientlib-all/vite/js/cf6255a2.chunk.js | 118 KB | 76 KB (65%) | ✓ | 1st |
| https://www.lufthansa.com/etc.clientlibs/clientlibs/granite/jquery.1fc733054ddb2e2fcd4a0f763671047b.js | 87 KB | 57 KB (66%) | ✗ | 1st |
| https://www.lufthansa.com/etc/designs/dcep/clientlib-all/vite/js/63ac1397.chunk.js | 74 KB | 45 KB (61%) | ✓ | 1st |
| https://www.lufthansa.com/etc/designs/dcep/clientlib-all/vite/js/d10bccbc.chunk.js | 52 KB | 45 KB (86%) | ✓ | 1st |
| https://www.lufthansa.com/digitalhangar/design-system/releases/v1.26.2/standalone/packages/maui-design-system.js | 308 KB | 43 KB (14%) | ✗ | 1st |
| https://tags.tiqcdn.com/utag/lufthansa/main/prod/utag.js | 120 KB | 39 KB (34%) | ✓ | 3rd |
| https://www.lufthansa.com/etc/designs/dcep/clientlib-all/vite/js/9792a05f.chunk.js | 66 KB | 34 KB (51%) | ✓ | 1st |
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
DHTTP CachingActionno-store (uncacheable)FIX
private, max-age=0, no-store, no-cache, must-revalidate, post-check=0, pre-check=0
| Directive | Value | Meaning |
|---|---|---|
| private | — | Only browser cache, not CDN/proxy |
| max-age | 0 | Cache for 0 seconds |
| no-store | — | Never cache this response |
| no-cache | — | Cache but always revalidate first |
| must-revalidate | — | Must recheck with server after expiry |
| post-check | 0 | |
| pre-check | 0 |
CImage OptimizationAction38 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
AThird-Party Impact34% third-party, 0 ms blockingPASS
A+Text CompressionAll text resources are compressedPASS
A+Font Loading22 fonts (1339 KB)PASS
Web fonts
22
1339 KB total
Render-blocking
0
of 22
Dominant font-display
swap
Most common across fonts
Font loading timeline
- Convert to woff2 for ~30% smaller file size
- Convert to woff2 for ~30% smaller file size
- Convert to woff2 for ~30% smaller file size
- Convert to woff2 for ~30% smaller file size
- Convert to woff2 for ~30% smaller file size
- 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
- Convert to woff2 for ~30% smaller file size
- Convert to woff2 for ~30% smaller file size
- Convert to woff2 for ~30% smaller file size
- Convert to woff2 for ~30% smaller file size
- Convert to woff2 for ~30% smaller file size
- Convert to woff2 for ~30% smaller file size
- Convert to woff2 for ~30% smaller file size
- Convert to woff2 for ~30% smaller file size
- Convert to woff2 for ~30% smaller file size
- Convert to woff2 for ~30% smaller file size
- Convert to woff2 for ~30% smaller file size
- Convert to woff2 for ~30% smaller file size
- Convert to woff2 for ~30% smaller file size
- Convert to woff2 for ~30% smaller file size
- 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 ~468 KB and ~936 ms
A+Resource CachingAll resources properly cachedPASS
A+Critical Rendering PathNo render-blocking resourcesPASS
A+Resource HintsNo optimization neededPASS
A+Green HostingWhether the site is served from green-energy infrastructurePASS
Green Hosting
This site is hosted on green energy infrastructure
Provider: Cloudflare
Network Waterfall515 requests over 0msINFO
Performance analysis not available for this result.
Third-Party Script CostPer-script blocking time, transfer cost, and cache headersINFO
| Script | Category | Execution | Transfer | Unused | Monthly Cost | Verdict |
|---|---|---|---|---|---|---|
Unattributable Unattributable | Other | 887ms | 0 KB | — | €10/mo | Costly |
shop.lufthansa.com shop.lufthansa.com | Other | 140ms | 16 KB | — | €2/mo | Optional |
tags.tiqcdn.com tags.tiqcdn.com | Other | 61ms | 120 KB | 34% | €1/mo | Optional |
These scripts may cost more than they're worth
- Unattributable adds 887ms and costs ~€10/month
Unattributable takes 887ms 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