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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
64
GRADE
D
FIX
3
REVIEW
2
PASS
1
INFO
0
Device:
Mobile Desktop
Checks
6
1 PASS 2 REVIEW 3 FIX
D
CO2 Per Page Load
Action
0.86g CO2 per view
FIX
0.86g CO2 per view
Info::
0.86g CO2 per page view
This page transfers 3.0 MB, producing an estimated 0.86g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.16g, network 0.15g, end-user device 0.55g.
Got: 0.86g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 103.1 kg CO2/year
With 10,000 page views per month, this page would generate approximately 103.1 kg of CO2 annually — equivalent to charging 12881 smartphones.

0.86g

Carbon Footprint per page view

✗ Above sustainability target (0.50g)

Cleaner than 43% of websites

Sustainable Web Design model v4 · Page size: 3.0 MB

Your site
0.86g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.16g
Network
0.15g
End-user device
0.55g
At 10,000 monthly views: Monthly: 8.6 kg · Annual: 103.1 kg · ≈ 12881 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 Apache HTTP Server✗CDN Not identified✗

Based on known provider commitments. Verify at thegreenwebfoundation.org

D
Carbon Budget
Action
57th percentile
FIX
57th percentile
Warning::
0.86g CO2 — above the median website (0.60g)
Heavier than an estimated 43% of websites. Reducing page weight, optimizing images, and removing unused JavaScript would lower the carbon footprint. See the Performance tab.
Info::
Estimated 57th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

0.86g

57th percentile

Cleaner than 43% of websites

✗ Above the median website

vs Median 43% more
vs Target 72% more
B
Transfer Efficiency
84% efficient
REVIEW
84% efficient
Info::
Transfer efficiency: 84%
An estimated 484 KB (16%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 484 KB of unused JavaScript. This wasted data produces 0.13g of unnecessary CO2 per page view.
84% efficient

Total waste: 484 KB (16% of page weight)

Unused JS 484 KB

0.13g unnecessary CO2 per visit

Actual transfer 3105 KB
Theoretical minimum 2620 KB
Potential savings 484 KB (0.13g CO2)

See Deep Analysis sections above for specific optimizations.

C
Green Hosting
Action
Whether the site is served from green-energy infrastructure
REVIEW

Green Hosting

No green hosting detected

A+
Repeat Visit Weight
99% cached
PASS
99% cached
Info::
99% reduction on repeat visits
Returning visitors download only 40 KB (vs 3105 KB first visit). 48 of 49 resources are served from browser cache, saving 0.85g CO2 per repeat visit.
Info::
Repeat visit: 0.01g CO2 (first visit: 0.86g)
First visit
3105 KB
Repeat visit
40 KB

99% reduction on repeat visits

Saving 0.85g CO2 per returning visitor

48 resources served from cache · 1 resources re-downloaded

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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