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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
70
GRADE
C
FIX
2
REVIEW
3
PASS
1
INFO
0
Device:
Mobile Desktop
Checks
6
1 PASS 3 REVIEW 2 FIX
D
Green Hosting
Action
Unknown
FIX
Unknown
Info::
Hosting provider could not be identified
Without knowing the provider, we cannot determine their energy sourcing. Check with your hosting provider about their renewable energy commitments.
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 HostingUnable to Determine
Hosting Not identified✗CDN Not identified✗

Based on known provider commitments. Verify at thegreenwebfoundation.org

D
Carbon Budget
Action
51th percentile
FIX
51th percentile
Warning::
0.64g CO2 — above the median website (0.60g)
Heavier than an estimated 49% of websites. Reducing page weight, optimizing images, and removing unused JavaScript would lower the carbon footprint. See the Performance tab.
Info::
Estimated 51th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

0.64g

51st percentile

Cleaner than 49% of websites

✗ Above the median website

vs Median 7% more
vs Target 29% more
B
CO2 Per Page Load
0.64g CO2 per view
REVIEW
0.64g CO2 per view
Info::
0.64g CO2 per page view
This page transfers 2.3 MB, producing an estimated 0.64g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.12g, network 0.11g, end-user device 0.41g.
Got: 0.64g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 77.3 kg CO2/year
With 10,000 page views per month, this page would generate approximately 77.3 kg of CO2 annually — equivalent to charging 9666 smartphones.

0.64g

Carbon Footprint per page view

✗ Above sustainability target (0.50g)

Cleaner than 49% of websites

Sustainable Web Design model v4 · Page size: 2.3 MB

Your site
0.64g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.12g
Network
0.11g
End-user device
0.41g
At 10,000 monthly views: Monthly: 6.4 kg · Annual: 77.3 kg · ≈ 9666 smartphone charges
B
Transfer Efficiency
85% efficient
REVIEW
85% efficient
Info::
Transfer efficiency: 85%
An estimated 354 KB (15%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 354 KB of unused JavaScript. This wasted data produces 0.10g of unnecessary CO2 per page view.
85% efficient

Total waste: 354 KB (15% of page weight)

Unused JS 354 KB

0.10g unnecessary CO2 per visit

Actual transfer 2330 KB
Theoretical minimum 1975 KB
Potential savings 354 KB (0.10g 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 21 KB (vs 2330 KB first visit). 42 of 43 resources are served from browser cache, saving 0.64g CO2 per repeat visit.
Info::
Repeat visit: 0.01g CO2 (first visit: 0.64g)
First visit
2330 KB
Repeat visit
21 KB

99% reduction on repeat visits

Saving 0.64g CO2 per returning visitor

42 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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