Audit overview
4 categories need attention: Performance, and 3 others.
Fix Priority Matrix
5 findingsQuick Wins
3High impact, low effort — start here.
Strategic
2High impact, requires investment.
Easy Improvements
0Small gains, minimal effort.
Nothing in this quadrant — good news.
Deprioritize
0Low impact, high effort — do last.
Nothing in this quadrant — good news.
Screenshots
Top Priorities (5)
Content-Security-Policy header is missing
Without a CSP, a single XSS bug can exfiltrate everything your users type — including credentials.
No Content-Security-Policy header found
Without a CSP, a single XSS bug can exfiltrate everything users type — credentials, payment data, session tokens.
Page weighs 14.4 MB (6.0 MB transferred)
Informational: total page weight (uncompressed) and bytes actually transferred over the wire.
102 link(s) with no accessible text
Links with no accessible text (empty <a></a>, image-only no alt, icon-only no aria-label) are unidentifiable to screen readers.
58 image-only link(s) without alt text
Image-only links with no alt are unidentifiable to screen-reader users — link's destination is invisible.
Business case
What fixing the audit's findings is worth -- and what ignoring them keeps costing.
Return on investment
CZK 7,700 investment → CZK 87,595/month returns + EUR 120,500,000 risk avoided
Figures combine localized regulatory fine ceilings, search/conversion value priced against local CPC, and bandwidth waste estimates. Results depend on implementation quality and audience composition. Not legal or financial advice.
Conversion barriers
7 barrier(s) likely increasing bounce by ~30%.
- Page takes 13.6s to loadUsers abandon at ~3s — you're 11.1s over the 2.5s threshold→ Optimize render-blocking resources, preload the hero image, and compress images
- Page feels frozen for 3.9sClicks on the primary CTA are ignored while JavaScript runs→ Break up long tasks; defer non-critical JavaScript to post-hydration
- 12 broken link(s) on the pageClicks land on 404s — trust drops and the session often ends→ Fix or remove the broken destinations surfaced on the Content tab
- No Content-Security-Policy headerHigher XSS blast radius — one compromised script can exfiltrate the checkout form→ Ship a reporting-only CSP first, then enforce once violations are clean
- No structured dataNo rich-result eligibility in Google — lower SERP CTR vs competitors with stars and prices→ Add JSON-LD for your page type (Product, Article, FAQPage, LocalBusiness, …)
Preliminary CRO audit — each barrier links to the tab with detailed analysis.
Remediation cost
Start here for the best return on investment
Cost by category
Cost by effort level
Adjust assumptions
Team composition
Multiplier applied to dev hours to reflect QA, design, and PM overhead. Use Dev only for solo work; Full team for projects with formal review processes.
Rates reflect fully-loaded developer cost including overhead
Warning:Cost of inaction
Compliance Risk
€120.500.000
- No privacy policy link detectedGDPR: EUR 10.000 – EUR 20.000.000
- Trackers detected but no cookie policy foundGDPR: EUR 5.000 – EUR 10.000.000
- Trackers detected but no cookie policy foundGDPR: EUR 10.000 – EUR 20.000.000
Bounce-Rate Cost
CZK 74.179 /mo
+29.7pp bounce · ~2,967 lost visitors/mo
CPC: CZK 25.00
Bandwidth Waste
CZK 35 /mo
18760.7 MB/mo × 1.860 CZK/GB
- Optimize transfer: save ~1.9 MB per page loadSaves CZK 35/mo
Compliance figures represent the statutory maximum fine for the most severe triggered category, capped per regulation — not the sum of per-finding penalties. Based on published regulatory fine ranges. This is not legal advice.
Unique monthly visitors from your analytics
Purchases, signups, or key actions
Optional — for revenue estimation
more engaged visitors from reduced bounce
Fix 5 critical issues to capture this value
How this is calculated
Based on Google/Deloitte research ("Milliseconds Make Millions") showing a ~7% bounce rate increase per additional second of LCP above the 2.5s "Good" threshold.
Your site's LCP: → estimated after fixes.
These are estimates based on industry research — actual results vary
Your data stays in your browser — nothing is sent to our servers
Lighthouse
Mobile
First Contentful Paint First Contentful Paint — how long until the browser renders the first piece of content. Under 1.8s is good.
6.84 s
Largest Contentful Paint Largest Contentful Paint — how long until the largest visible element loads. Under 2.5s is good.
13.61 s
Total Blocking Time Total Blocking Time — total time the main thread was blocked, preventing user input. Under 200ms is good.
3.90 s
Cumulative Layout Shift Cumulative Layout Shift — measures visual stability. How much the page layout shifts during loading. Under 0.1 is good.
0.098
Speed Index Speed Index — how quickly content is visually displayed during load. Under 3.4s is good.
17.73 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.
34.17 s
Desktop
First Contentful Paint First Contentful Paint — how long until the browser renders the first piece of content. Under 1.8s is good.
3.21 s
Largest Contentful Paint Largest Contentful Paint — how long until the largest visible element loads. Under 2.5s is good.
4.70 s
Total Blocking Time Total Blocking Time — total time the main thread was blocked, preventing user input. Under 200ms is good.
670 ms
Cumulative Layout Shift Cumulative Layout Shift — measures visual stability. How much the page layout shifts during loading. Under 0.1 is good.
0.012
Speed Index Speed Index — how quickly content is visually displayed during load. Under 3.4s is good.
7.96 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.
9.93 s
Categories
8Performance
Page weighs 14.4 MB (6.0 MB transferred)
Security
Content-Security-Policy header is missing
Accessibility
102 link(s) with no accessible text
SEO
All checks pass
Infrastructure
All checks pass
Compliance
All checks pass
Content
All checks pass
Sustainability
All checks pass
How you compare
Where this site stands against peers running the same stack.
Top 10% of core-js sites score 84+ on Sustainability; you're at 56 — closing this gap is the highest-leverage improvement.
Top 10% of Facebook sites score 83+ on Performance; you're at 67 — closing this gap is the highest-leverage improvement.
Technology stack
Facebook, hosted on Snowplow Analytics, with Envoy CDN
Stack Architecture
Gemius 
Google Analytics 
Google Tag Manager 
PostHog 
Goober Google Search Console HSTS 
Open Graph 
RSS 
Sentry 
Tailwind CSS 
Underscore.js 4.17.21
core-js 3.39.0
Envoy 
Snowplow Analytics All Detected Technologies (16)
Envoy is an open-source edge and service proxy, designed for cloud-native applications.
Snowplow is an open-source behavioral data management platform for businesses.
Goober is a minified CSS-in-JS styling solution.
HTTP Strict Transport Security (HSTS) informs browsers that the site should only be accessed using HTTPS.
Open Graph is a protocol that is used to integrate any web page into the social graph.
RSS is a family of web feed formats used to publish frequently updated works—such as blog entries, news headlines, audio, and video—in a standardized format.
Sentry is an open-source platform for workflow productivity, aggregating errors from across the stack in real time.
Underscore.js is a JavaScript library which provides utility functions for common programming tasks. It is comparable to features provided by Prototype.js and the Ruby language, but opts for a functional programming design instead of extending object prototypes.
core-js is a modular standard library for JavaScript, with polyfills for cutting-edge ECMAScript features.
Google Analytics is a free web analytics service that tracks and reports website traffic.
Google Tag Manager is a tag management system (TMS) that allows you to quickly and easily update measurement codes and related code fragments collectively known as tags on your website or mobile app.
PostHog is the open-source, all-in-one product analytics platform.
Observations (2)
No build tool detected
A framework (Facebook) was detected but no bundler was identified. The build tool may not be detectable from output patterns, or the site may use the framework's built-in bundler.
Complex technology stack detected
16 technologies identified. A complex stack increases maintenance burden and attack surface. Consider whether all components are actively needed.
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Fix Plan
Three-week roadmap to ship the audit's findings, with one-click copy targets for your tracker.
Three-week fix plan
2 sprints · 7h total → projected B (82)
Sprint 1: Quick Wins
+6Highest ROI — low effort, high impact
- · Page weighs 14.4 MB (6.0 MB transferred)
- · 102 link(s) with no accessible text
- · 58 image-only link(s) without alt text
Sprint 2: Core Fixes
+5Medium effort, high structural impact
- · Content-Security-Policy header is missing
- · No Content-Security-Policy header found