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https://roccosiffredi.net

Sustainability

· 8 checks — CO2 emissions, green hosting, repeat-visit weight, carbon budget, and transfer efficiency rolled into one auditable list.
SCORE
74
GRADE
C
FIX
1
REVIEW
4
PASS
2
INFO
1
Device:
Mobile Desktop
Checks
8
2 PASS 4 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
Carbon Budget
32th percentile
REVIEW
32th percentile
Info::
0.42g CO2 — below the sustainability target of 0.50g
Cleaner than an estimated 68% of websites analyzed. This page meets the Web Sustainability Guidelines target.
Info::
Estimated 32th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

0.42g

32nd percentile

Cleaner than 68% of websites

✓ Below the Web Sustainability Guidelines target

vs Median 30% cleaner ✓
vs Target 16% cleaner ✓
C
Transfer Efficiency
Action
69% efficient
REVIEW
69% efficient
Warning::
Transfer efficiency: 69%
An estimated 469 KB (31%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 469 KB of unused JavaScript. This wasted data produces 0.13g of unnecessary CO2 per page view.
69% efficient

Total waste: 469 KB (31% of page weight)

Unused JS 469 KB

0.13g unnecessary CO2 per visit

Actual transfer 1526 KB
Theoretical minimum 1057 KB
Potential savings 469 KB (0.13g 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
0.42g CO2 per view
PASS
0.42g CO2 per view
Info::
0.42g CO2 per page view
This page transfers 1.5 MB, producing an estimated 0.42g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.08g, network 0.07g, end-user device 0.27g.
Got: 0.42g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 50.7 kg CO2/year
With 10,000 page views per month, this page would generate approximately 50.7 kg of CO2 annually — equivalent to charging 6332 smartphones.

0.42g

Carbon Footprint per page view

✓ Below sustainability target (0.50g)

Cleaner than 68% of websites

Sustainable Web Design model v4 · Page size: 1.5 MB

Your site
0.42g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.08g
Network
0.07g
End-user device
0.27g
At 10,000 monthly views: Monthly: 4.2 kg · Annual: 50.7 kg · ≈ 6332 smartphone charges
A+
Repeat Visit Weight
99% cached
PASS
99% cached
Info::
99% reduction on repeat visits
Returning visitors download only 16 KB (vs 1526 KB first visit). 87 of 89 resources are served from browser cache, saving 0.42g CO2 per repeat visit.
Info::
Repeat visit: 0.00g CO2 (first visit: 0.42g)
First visit
1526 KB
Repeat visit
16 KB

99% reduction on repeat visits

Saving 0.42g CO2 per returning visitor

87 resources served from cache · 2 resources re-downloaded

Image Optimization
33 images, 988 KB total, 0 KB wasted
INFO

Image Optimization Audit

Total Images

33

Total Size

988 KB

23 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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