Browsers will use heuristic caching, which can be unpredictable. Set explicit cache headers.
No Cache-Control header
Adding a Cache-Control header can significantly improve repeat-visit performance.
C
Page Weight Budget
Action
1.6 MB transferred, 145 requests
REVIEW
1.6 MB transferred, 145 requests
Info::
i
Page weighs 5.4 MB (1.6 MB transferred)
Warning::
!
JavaScript is 795 KB — consider code splitting or lazy loading
Large JavaScript bundles delay interactivity. Split code by route or defer non-critical scripts.
Got: 795 KB
Info::
i
Fonts are 327 KB — consider subsetting or using system fonts
Subset fonts to include only used characters, or switch to system font stacks.
Got: 327 KB
Warning::
!
145 HTTP requests — consider bundling or reducing
Each request adds latency. Bundle small files, use sprites, or eliminate unnecessary requests.
Info::
i
Estimated 0.34 g CO2 per page load
1.6 MBtransferred
145 requests
0.34 g CO2 per page load
JavaScript795.3 KiB47%
Fonts326.5 KiB19%
Images226.8 KiB14%
HTML154.7 KiB9%
Other127.2 KiB8%
Other25.6 KiB2%
CSS17.3 KiB1%
Other5.8 KiB0%
Other725 B0%
Other197 B0%
Other0 B0%
02.4 MB4.9 MB
Approaching limit
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
Subset fonts to include only used characters, or switch to system font stacks.
Why this matters
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.
Why this matters
High HTTP request count — bundling, sprite-ing, and HTTP/2 server push can reduce per-request overhead.
Source: web.dev
B
Image Optimization
13 images, 0 KB saveable
REVIEW
13 images, 0 KB saveable
Info::
✓
All images are well-optimized
13images227 KB
0oversized-0 KB
6legacy format
0missing dimensionsCLS risk
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
20 fonts (327 KB)
PASS
20 fonts (327 KB)
Info::
i
20 font(s) use font-display: swap (FOUT risk but functional)
Web fonts
20
327 KB total
Render-blocking
0
of 20
Dominant font-display
swap
Most common across fonts
Font loading timeline
TransferFOIT (block)FOUT (swap)
franklingothic-book-bas...woff2swap
Size12 KB
Load time40 ms
Start559 ms
RiskFOUT — text flashes from fallback to web font
Abril_Text_Regular-basi...woff2swap
Size30 KB
Load time66 ms
Start559 ms
RiskFOUT — text flashes from fallback to web font
Abril_Text_Bold-basic.e...woff2swap
Size32 KB
Load time79 ms
Start559 ms
RiskFOUT — text flashes from fallback to web font
franklingothic-book-bas...woff2swap
Size0 KB
Load time6 ms
Start643 ms
RiskFOUT — text flashes from fallback to web font
Abril_Text_Regular-basi...woff2swap
Size0 KB
Load time7 ms
Start643 ms
RiskFOUT — text flashes from fallback to web font
Abril_Text_Bold-basic.e...woff2swap
Size0 KB
Load time12 ms
Start646 ms
RiskFOUT — text flashes from fallback to web font
franklingothic-med-basi...woff2swap
Size12 KB
Load time38 ms
Start740 ms
RiskFOUT — text flashes from fallback to web font
Abril_Text_BoldItalic-b...woff2swap
Size36 KB
Load time40 ms
Start741 ms
RiskFOUT — text flashes from fallback to web font
Abril_Text_Italic-basic...woff2swap
Size34 KB
Load time37 ms
Start741 ms
RiskFOUT — text flashes from fallback to web font
franklingothic-med-exte...woff2swap
Size15 KB
Load time28 ms
Start741 ms
RiskFOUT — text flashes from fallback to web font
Abril_Text_Regular-exte...woff2swap
Size23 KB
Load time23 ms
Start835 ms
RiskFOUT — text flashes from fallback to web font
Abril_Text_Bold-extende...woff2swap
Size25 KB
Load time20 ms
Start933 ms
RiskFOUT — text flashes from fallback to web font
franklingothic-book-ext...woff2swap
Size15 KB
Load time25 ms
Start1.2 s
RiskFOUT — text flashes from fallback to web font
franklingothic-book-bas...woff2swap
Size0 KB
Load time1 ms
Start2.1 s
RiskFOUT — text flashes from fallback to web font
Abril_Text_Bold-basic.e...woff2swap
Size0 KB
Load time3 ms
Start2.2 s
RiskFOUT — text flashes from fallback to web font
Abril_Text_Regular-basi...woff2swap
Size0 KB
Load time3 ms
Start2.2 s
RiskFOUT — text flashes from fallback to web font
abril_text_bold-webfont...woff2swap
Size29 KB
Load time54 ms
Start3.3 s
RiskFOUT — text flashes from fallback to web font
abril_text_regular-webf...woff2swap
Size28 KB
Load time22 ms
Start3.3 s
RiskFOUT — text flashes from fallback to web font
franklingothic-med-webf...woff2swap
Size17 KB
Load time24 ms
Start3.3 s
RiskFOUT — text flashes from fallback to web font
franklingothic-book-web...woff2swap
Size17 KB
Load time19 ms
Start3.3 s
RiskFOUT — 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
56 hints, 0 missing preconnects
PASS
56 hints, 0 missing preconnects
Info::
✓
Page uses 56 resource hint(s)
Current Resource Hints
preconnect—
preload
10
dns-prefetch—
prefetch
+36
46
56 resource hints configured
A+
Render-Blocking Resources
No render-blocking resources detected
PASS
No render-blocking resources detected
Info::
✓
No render-blocking resources detected in <head>
A+
Third-Party Resources
No third-party resources detected
PASS
No third-party resources detected
A+
Green Hosting
Whether the site is served from green-energy infrastructure
PASS
Green Hosting
This site is hosted on green energy infrastructure
Provider: Cloudflare
Network Waterfall
145 requests over 4792ms
INFO
HTML JavaScript CSS Images Fonts XHR/Fetch Other
Third-Party Script Cost
Per-script blocking time, transfer cost, and cache headers
INFO
100%of JavaScript execution is third-party
First-party Third-party7672ms · 777KB · €83/mo
Script
Category
Execution
Transfer
Unused
Monthly Cost
Verdict
www.tagesspiegel.de
www.tagesspiegel.de
Other
2092ms
144 KB
—
€23/mo
Costly
Unattributable
Unattributable
Other
996ms
0 KB
—
€11/mo
Costly
www.tagesspiegel.de
www.tagesspiegel.de
Other
946ms
0 KB
—
€10/mo
Costly
cmp-sp.tagesspiegel.de
cmp-sp.tagesspiegel.de
Other
732ms
80 KB
67%
€8/mo
Costly
cdn.piano.io
cdn.piano.io
Other
660ms
133 KB
52%
€7/mo
Costly
Google Tag Manager
www.googletagmanager.com
Tag Manager
528ms
179 KB
41%
€6/mo
Costly
cdnjs
cdnjs.cloudflare.com
CDN
427ms
30 KB
—
€5/mo
Costly
cdn.privacy-mgmt.com
cdn.privacy-mgmt.com
Other
303ms
54 KB
41%
€3/mo
Costly
cl.k5a.io
cl.k5a.io
Other
258ms
31 KB
—
€3/mo
Costly
vx.tagesspiegel.de
vx.tagesspiegel.de
Other
185ms
44 KB
70%
€2/mo
Optional
cdn.cxense.com
cdn.cxense.com
Other
148ms
38 KB
57%
€2/mo
Optional
cmp-sp.tagesspiegel.de
cmp-sp.tagesspiegel.de
Other
144ms
2 KB
—
€2/mo
Optional
www.tagesspiegel.de
www.tagesspiegel.de
Other
100ms
0 KB
—
€1/mo
Optional
vx.tagesspiegel.de
vx.tagesspiegel.de
Other
79ms
8 KB
—
€1/mo
Optional
cp.tagesspiegel.de
cp.tagesspiegel.de
Other
75ms
35 KB
—
€1/mo
Optional
www.tagesspiegel.de
Other
Costly
Execution2092ms
Transfer144 KB
Monthly Cost€23/mo
Unattributable
Other
Costly
Execution996ms
Transfer0 KB
Monthly Cost€11/mo
www.tagesspiegel.de
Other
Costly
Execution946ms
Transfer0 KB
Monthly Cost€10/mo
cmp-sp.tagesspiegel.de
Other
Costly
Execution732ms
Transfer80 KB
Unused67%
Monthly Cost€8/mo
cdn.piano.io
Other
Costly
Execution660ms
Transfer133 KB
Unused52%
Monthly Cost€7/mo
Google Tag Manager
Tag Manager
Costly
Execution528ms
Transfer179 KB
Unused41%
Monthly Cost€6/mo
cdnjs
CDN
Costly
Execution427ms
Transfer30 KB
Monthly Cost€5/mo
cdn.privacy-mgmt.com
Other
Costly
Execution303ms
Transfer54 KB
Unused41%
Monthly Cost€3/mo
cl.k5a.io
Other
Costly
Execution258ms
Transfer31 KB
Monthly Cost€3/mo
vx.tagesspiegel.de
Other
Optional
Execution185ms
Transfer44 KB
Unused70%
Monthly Cost€2/mo
cdn.cxense.com
Other
Optional
Execution148ms
Transfer38 KB
Unused57%
Monthly Cost€2/mo
cmp-sp.tagesspiegel.de
Other
Optional
Execution144ms
Transfer2 KB
Monthly Cost€2/mo
www.tagesspiegel.de
Other
Optional
Execution100ms
Transfer0 KB
Monthly Cost€1/mo
vx.tagesspiegel.de
Other
Optional
Execution79ms
Transfer8 KB
Monthly Cost€1/mo
cp.tagesspiegel.de
Other
Optional
Execution75ms
Transfer35 KB
Monthly Cost€1/mo
These scripts may cost more than they're worth
www.tagesspiegel.de adds 2092ms and costs ~€23/month
Unattributable adds 996ms and costs ~€11/month
www.tagesspiegel.de adds 946ms and costs ~€10/month
cmp-sp.tagesspiegel.de adds 732ms and costs ~€8/month
cdn.piano.io adds 660ms and costs ~€7/month
Google Tag Manager adds 528ms and costs ~€6/month
cdnjs adds 427ms and costs ~€5/month
cdn.privacy-mgmt.com adds 303ms and costs ~€3/month
cl.k5a.io adds 258ms and costs ~€3/month
100% of JavaScript execution time is spent on third-party scripts. Consider auditing which scripts are essential.
Why this matters
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.tagesspiegel.de takes 2092ms 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
Unattributable takes 996ms 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
www.tagesspiegel.de takes 946ms 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
cmp-sp.tagesspiegel.de takes 732ms 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
67% of cmp-sp.tagesspiegel.de'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
cdn.piano.io takes 660ms 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
52% of cdn.piano.io'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
Google Tag Manager takes 528ms 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
cdnjs takes 427ms 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
cdn.privacy-mgmt.com takes 303ms 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
cl.k5a.io takes 258ms 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
70% of vx.tagesspiegel.de'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
57% of cdn.cxense.com'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.