Performance
· 17 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.
7.80 s
Largest Contentful Paint Largest Contentful Paint — how long until the largest visible element loads. Under 2.5s is good.
10.65 s
Total Blocking Time Total Blocking Time — total time the main thread was blocked, preventing user input. Under 200ms is good.
58 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.
7.80 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.
10.73 s
Page Load Progression
DThird-Party ImpactAction100% third-party, 0 ms blockingFIX
DPage Weight InventoryAction48 resources · 1.6 MB · 86 KB savings availableFIX
~86.1 KiB of savings available
| # | Resource | Type | Size | Cache | Unused | 3rd party | Issues |
|---|---|---|---|---|---|---|---|
| — | — | ||||||
| 48 resources | 1.6 MiB | ||||||
FHTTP CachingActionNo cache headersFIX
No Cache-Control header
Adding a Cache-Control header can significantly improve repeat-visit performance.
CPage Weight BudgetAction1.6 MB transferred, 48 requestsREVIEW
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
Remove unused CSS rules with tools like PurgeCSS to reduce stylesheet size.
CSS bundle is large — purge unused styles (PurgeCSS, Tailwind JIT) to reduce CSS payload.
Source: web.dev
CJS Execution CostAction1396ms total JS executionREVIEW
Main Thread Breakdown
| Script | Total | Scripting | Parse/Compile | Party |
|---|---|---|---|---|
| https://www.bosch.com/media/tech/scripts/main.js?ver=1772529817623 | 331ms | 123ms | 16ms | 3rd |
| Unattributable | 319ms | 15ms | 0ms | 3rd |
| https://www.googletagmanager.com/gtm.js?id=GTM-TBM8RNC | 254ms | 212ms | 35ms | 3rd |
| https://www.bosch.com/ | 219ms | 11ms | 4ms | 3rd |
| https://dock.ui.bosch.tech/releases/4-latest/build/p-88b2d8c0.js | 184ms | 101ms | 0ms | 3rd |
| https://www.bosch.com/media/tech/scripts/vendors.js?ver=1772529817623 | 88ms | 80ms | 5ms | 3rd |
BJS Bundles10 scripts, 86 KB unusedREVIEW
Downloaded but never executed on this page.
| Script | Size | Unused | Minified | Party |
|---|---|---|---|---|
| https://www.googletagmanager.com/gtm.js?id=GTM-TBM8RNC | 142 KB | 61 KB (43%) | ✓ | 3rd |
| https://www.bosch.com/media/tech/scripts/main.js?ver=1772529817623 | 48 KB | 25 KB (54%) | ✓ | 3rd |
| https://dock.ui.bosch.tech/releases/4-latest/build/dock-privacy-settings.esm.js | 3 KB | — | ✓ | 3rd |
| https://www.bosch.com/media/tech/scripts/react.js?ver=1772529817623 | 42 KB | — | ✓ | 3rd |
| https://www.bosch.com/media/tech/scripts/vendors.js?ver=1772529817623 | 26 KB | — | ✓ | 3rd |
| https://dock.ui.bosch.tech/releases/4-latest/build/p-88b2d8c0.js | 7 KB | — | ✓ | 3rd |
| https://sst.bosch.com/echo.js | 5 KB | — | ✓ | 3rd |
| https://dock.ui.bosch.tech/releases/4-latest/build/p-f0149d54.entry.js | 28 KB | — | ✓ | 3rd |
| https://dock.ui.bosch.tech/releases/4-latest/build/p-d2842e67.js | 1 KB | — | ✓ | 3rd |
| https://dock.ui.bosch.tech/releases/4-latest/build/p-f4de5ca1.js | 1 KB | — | ✓ | 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
CGreen HostingActionWhether the site is served from green-energy infrastructureREVIEW
Green Hosting
No green hosting detected
A+Text CompressionAll text resources are compressedPASS
A+Image Optimization16 images, 0 KB saveablePASS
A+Font Loading5 fonts (667 KB)PASS
Web fonts
5
667 KB total
Render-blocking
0
of 5
Dominant font-display
swap
Most common across fonts
Font loading timeline
- 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 ~216 KB and ~432 ms
A+Resource CachingAll resources properly cachedPASS
A+Critical Rendering PathNo render-blocking resourcesPASS
A+Resource Hints3 hints, 0 missing preconnectsPASS
Current Resource Hints
3 resource hints configured
A+Render-Blocking ResourcesNo render-blocking resources detectedPASS
A+Third-Party ResourcesNo third-party resources detectedPASS
Network Waterfall48 requests over 2398msINFO
Third-Party Script CostPer-script blocking time, transfer cost, and cache headersINFO
| Script | Category | Execution | Transfer | Unused | Monthly Cost | Verdict |
|---|---|---|---|---|---|---|
www.bosch.com www.bosch.com | Other | 331ms | 48 KB | 54% | €4/mo | Costly |
Unattributable Unattributable | Other | 319ms | 0 KB | — | €3/mo | Costly |
Google Tag Manager www.googletagmanager.com | Tag Manager | 254ms | 142 KB | 43% | €3/mo | Costly |
www.bosch.com www.bosch.com | Other | 219ms | 20 KB | — | €2/mo | Costly |
dock.ui.bosch.tech dock.ui.bosch.tech | Other | 184ms | 7 KB | — | €2/mo | Optional |
www.bosch.com www.bosch.com | Other | 88ms | 26 KB | — | €1/mo | Optional |
These scripts may cost more than they're worth
- www.bosch.com adds 331ms and costs ~€4/month
- Unattributable adds 319ms and costs ~€3/month
- Google Tag Manager adds 254ms and costs ~€3/month
- www.bosch.com adds 219ms 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.bosch.com takes 331ms 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
54% of www.bosch.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
Unattributable takes 319ms 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 254ms 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.bosch.com takes 219ms 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