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https://www.donsp.sk

Sustainability

· 8 checks — CO2 emissions, green hosting, repeat-visit weight, carbon budget, and transfer efficiency rolled into one auditable list.
SCORE
80
GRADE
B
FIX
1
REVIEW
3
PASS
3
INFO
1
Device:
Mobile Desktop
Checks
8
3 PASS 3 REVIEW 1 FIX
D
Green Hosting
Action
Not green
FIX
Not green
Info::
No confirmed renewable energy commitment detected
Consider providers like Cloudflare, Google Cloud, or Vercel that match 100% of their energy use with renewables.
Info::
Green hosting status based on known provider commitments
Green hosting detection uses a curated database of provider renewable energy commitments. This is not a real-time verification. For authoritative checks, visit thegreenwebfoundation.org.
Green HostingNot Green Hosted
Hosting Apache HTTP Server✗CDN Not identified✗

Based on known provider commitments. Verify at thegreenwebfoundation.org

B
Transfer Efficiency
86% efficient
REVIEW
86% efficient
Info::
Transfer efficiency: 86%
An estimated 132 KB (14%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 132 KB of unused JavaScript. This wasted data produces 0.04g of unnecessary CO2 per page view.
86% efficient

Total waste: 132 KB (14% of page weight)

Unused JS 132 KB

0.04g unnecessary CO2 per visit

Actual transfer 940 KB
Theoretical minimum 808 KB
Potential savings 132 KB (0.04g CO2)

See Deep Analysis sections above for specific optimizations.

B
Web Font Weight Variants
No detectable Google Fonts weights
REVIEW
No detectable Google Fonts weights
Info::
No detectable Google Fonts weights
The analyzer detects font weights via Google Fonts URL parameters (~70% of font-using sites). Self-hosted fonts and non-Google CDN fonts aren't visible to URL-based detection. If you self-host fonts, manually audit how many @font-face weights you ship -- 2-3 weights per family is typically enough; 5+ is usually unused payload.
C
Green Hosting
Action
Whether the site is served from green-energy infrastructure
REVIEW

Green Hosting

No green hosting detected

A
CO2 Per Page Load
0.26g CO2 per view
PASS
0.26g CO2 per view
Info::
0.26g CO2 per page view
This page transfers 0.9 MB, producing an estimated 0.26g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.05g, network 0.04g, end-user device 0.17g.
Got: 0.26g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 31.2 kg CO2/year
With 10,000 page views per month, this page would generate approximately 31.2 kg of CO2 annually — equivalent to charging 3902 smartphones.

0.26g

Carbon Footprint per page view

✓ Below sustainability target (0.50g)

Cleaner than 84% of websites

Sustainable Web Design model v4 · Page size: 0.9 MB

Your site
0.26g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.05g
Network
0.04g
End-user device
0.17g
At 10,000 monthly views: Monthly: 2.6 kg · Annual: 31.2 kg · ≈ 3902 smartphone charges
A+
Repeat Visit Weight
96% cached
PASS
96% cached
Info::
96% reduction on repeat visits
Returning visitors download only 34 KB (vs 940 KB first visit). 57 of 58 resources are served from browser cache, saving 0.25g CO2 per repeat visit.
Info::
Repeat visit: 0.01g CO2 (first visit: 0.26g)
First visit
940 KB
Repeat visit
34 KB

96% reduction on repeat visits

Saving 0.25g CO2 per returning visitor

57 resources served from cache · 1 resources re-downloaded

A
Carbon Budget
16th percentile
PASS
16th percentile
Info::
0.26g CO2 — below the sustainability target of 0.50g
Cleaner than an estimated 84% of websites analyzed. This page meets the Web Sustainability Guidelines target.
Info::
Estimated 16th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

0.26g

16th percentile

Cleaner than 84% of websites

✓ Below the Web Sustainability Guidelines target

vs Median 57% cleaner ✓
vs Target 48% cleaner ✓
Image Optimization
34 images, 2184 KB total, 0 KB wasted
INFO

Image Optimization Audit

Total Images

34

Total Size

2184 KB

17 missing dimensions 1 missing lazy loading
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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