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https://www.vivaldi.com

Performance

· 14 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.
SCORE
89
GRADE
B
FIX
2
REVIEW
2
PASS
8
INFO
2

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

Mobile Desktop
97
Performance Overall performance score (0–100) based on Core Web Vitals and other metrics. 90+ is good.
96
Accessibility Measures how accessible the page is for users with disabilities. Checks color contrast, ARIA labels, and semantic HTML.
100
Best Practices Checks for modern web development best practices including HTTPS, no console errors, and secure JavaScript.
92
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.

773 ms

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

1.12 s

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

0 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.

1.00 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.

1.12 s

Page Load Progression

375 ms
750 ms
1.1 s
1.5 s
1.9 s
2.2 s
2.6 s
3.0 s
Checks
14
8 PASS 2 REVIEW 2 FIX
D
Third-Party Impact
Action
100% third-party, 0 ms blocking
FIX
100% third-party, 0 ms blocking
Warning::
Third-party code accounts for 100% of page weight (719.2 KiB of 719.4 KiB)
Info::
Third-party blocking time is low (0 ms)
100%
First-party Third-party
F
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.

No Cache-Control header

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

B
Image Optimization
25 images, 0 KB saveable
REVIEW
25 images, 0 KB saveable
Info::
All images are well-optimized
25 images 602 KB
0 oversized -0 KB
11 legacy format
0 missing dimensions CLS risk
B
JS Execution Cost
720ms total JS execution
REVIEW
720ms total JS execution
Warning::
https://vivaldi.com/: 398ms CPU time
Warning::
Unattributable: 322ms CPU time
Warning::
Third-party scripts: 720ms (100% of total)

Main Thread Breakdown

Other 75% Style & Layout 11% Script Evaluation 8% Rendering 3%
ScriptTotalScriptingParse/CompileParty
https://vivaldi.com/398ms7ms2ms3rd
Unattributable322ms5ms0ms3rd
A
Page Weight Budget
719 KB transferred, 38 requests
PASS
719 KB transferred, 38 requests
Info::
Page weighs 1.0 MB (719 KB transferred)
Info::
38 HTTP requests
Info::
Estimated 0.15 g CO2 per page load
719 KB / 2.4 MB budget
719 KB transferred
38 requests
0.15 g CO2 per page load
Images 602.0 KiB 84%
JavaScript 74.5 KiB 10%
HTML 23.0 KiB 3%
CSS 16.9 KiB 2%
Other 1.2 KiB 0%
Other 1.0 KiB 0%
Other 804 B 0%
0 2.4 MB 4.9 MB
Under budget
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
No web fonts (system fonts)
PASS
No web fonts (system fonts)
Info::
No web fonts loaded — system fonts are fastest
No web fonts loaded — system fonts are optimal.
A+
JS Bundles
6 scripts, 0 KB unused
PASS
6 scripts, 0 KB unused
0 KB unused JavaScript

Downloaded but never executed on this page.

ScriptSizeUnusedMinifiedParty
https://vivaldi.com/wp-content/themes/vivaldicom-theme/js/platform-detect.js?ver=17297518390 KB—✓3rd
https://vivaldi.com/wp-content/vivaldi-versions.js?ver=17758077551 KB—✓3rd
https://vivaldi.com/wp-includes/js/jquery/jquery.min.js?ver=3.7.130 KB—✓3rd
https://vivaldi.com/wp-content/themes/vivaldicom-theme/js/main.js?ver=176797089015 KB—✓3rd
https://vivaldi.com/rep2/script.js2 KB—✓3rd
https://vivaldi.com/rep/rep.js?227 KB—✓3rd
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
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
38 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
100% of JavaScript execution is third-party
First-party Third-party 720ms · 23KB · €8/mo
vivaldi.com
Other
Costly
Execution 398ms
Transfer 23 KB
Monthly Cost €4/mo
Unattributable
Other
Costly
Execution 322ms
Transfer 0 KB
Monthly Cost €4/mo

These scripts may cost more than they're worth

  • vivaldi.com adds 398ms and costs ~€4/month
  • Unattributable adds 322ms and costs ~€4/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

vivaldi.com takes 398ms 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 322ms 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

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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