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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
59
GRADE
D
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
2.45g CO2 per view
FIX
2.45g CO2 per view
Critical::
2.45g CO2 per page view
This page transfers 8.6 MB, producing an estimated 2.45g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.45g, network 0.42g, end-user device 1.57g.
Got: 2.45g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 293.9 kg CO2/year
With 10,000 page views per month, this page would generate approximately 293.9 kg of CO2 annually — equivalent to charging 36732 smartphones.

2.45g

Carbon Footprint per page view

✗ Above sustainability target (0.50g)

Cleaner than 5% of websites

Sustainable Web Design model v4 · Page size: 8.6 MB

Your site
2.45g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.45g
Network
0.42g
End-user device
1.57g
At 10,000 monthly views: Monthly: 24.5 kg · Annual: 293.9 kg · ≈ 36732 smartphone charges
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

F
Carbon Budget
Action
95th percentile
FIX
95th percentile
Warning::
2.45g 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

2.45g

95th percentile

Cleaner than 5% of websites

✗ Above the median website

vs Median 308% more
vs Target 390% 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
98% cached
PASS
98% cached
Info::
98% reduction on repeat visits
Returning visitors download only 150 KB (vs 8854 KB first visit). 163 of 164 resources are served from browser cache, saving 2.41g CO2 per repeat visit.
Info::
Repeat visit: 0.04g CO2 (first visit: 2.45g)
First visit
8854 KB
Repeat visit
150 KB

98% reduction on repeat visits

Saving 2.41g CO2 per returning visitor

163 resources served from cache · 1 resources re-downloaded

A+
Transfer Efficiency
98% efficient
PASS
98% efficient
Info::
Transfer efficiency: 98%
Only 139 KB of potential savings identified. Your page is well-optimized for size.
98% efficient

Total waste: 139 KB (2% of page weight)

Unused JS 139 KB

0.04g unnecessary CO2 per visit

Actual transfer 8854 KB
Theoretical minimum 8714 KB
Potential savings 139 KB (0.04g 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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