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Sustainability

· 6 checks — CO2 emissions, green hosting, repeat-visit weight, carbon budget, and transfer efficiency rolled into one auditable list.
SCORE
84
GRADE
B
FIX
3
REVIEW
1
PASS
2
INFO
0
Device:
Mobile Desktop
Checks
6
2 PASS 1 REVIEW 3 FIX
F
CO2 Per Page Load
Action
5.16g CO2 per view
FIX
5.16g CO2 per view
Critical::
5.16g CO2 per page view
This page transfers 18.2 MB, producing an estimated 5.16g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.96g, network 0.89g, end-user device 3.31g.
Got: 5.16g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 619.5 kg CO2/year
With 10,000 page views per month, this page would generate approximately 619.5 kg of CO2 annually — equivalent to charging 77433 smartphones.

5.16g

Carbon Footprint per page view

✗ Above sustainability target (0.50g)

Cleaner than 5% of websites

Sustainable Web Design model v4 · Page size: 18.2 MB

Your site
5.16g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.96g
Network
0.89g
End-user device
3.31g
At 10,000 monthly views: Monthly: 51.6 kg · Annual: 619.5 kg · ≈ 77433 smartphone charges
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 Not identified✗CDN Incapsula✗

Based on known provider commitments. Verify at thegreenwebfoundation.org

F
Carbon Budget
Action
95th percentile
FIX
95th percentile
Warning::
5.16g CO2 — above the median website (0.60g)
Heavier than an estimated 5% of websites. Reducing page weight, optimizing images, and removing unused JavaScript would lower the carbon footprint. See the Performance tab.
Info::
Estimated 95th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

5.16g

95th percentile

Cleaner than 5% of websites

✗ Above the median website

vs Median 760% more
vs Target 932% more
C
Green Hosting
Action
Whether the site is served from green-energy infrastructure
REVIEW

Green Hosting

No green hosting detected

A+
Repeat Visit Weight
100% cached
PASS
100% cached
Info::
100% reduction on repeat visits
Returning visitors download only 21 KB (vs 18665 KB first visit). 130 of 131 resources are served from browser cache, saving 5.16g CO2 per repeat visit.
Info::
Repeat visit: 0.01g CO2 (first visit: 5.16g)
First visit
18665 KB
Repeat visit
21 KB

100% reduction on repeat visits

Saving 5.16g CO2 per returning visitor

130 resources served from cache · 1 resources re-downloaded

A+
Transfer Efficiency
97% efficient
PASS
97% efficient
Info::
Transfer efficiency: 97%
Only 521 KB of potential savings identified. Your page is well-optimized for size.
97% efficient

Total waste: 521 KB (3% of page weight)

Unused JS 521 KB

0.14g unnecessary CO2 per visit

Actual transfer 18665 KB
Theoretical minimum 18143 KB
Potential savings 521 KB (0.14g CO2)

See Deep Analysis sections above for specific optimizations.

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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