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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
2.58g CO2 per view
FIX
2.58g CO2 per view
Critical::
2.58g CO2 per page view
This page transfers 9.1 MB, producing an estimated 2.58g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.48g, network 0.45g, end-user device 1.65g.
Got: 2.58g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 309.3 kg CO2/year
With 10,000 page views per month, this page would generate approximately 309.3 kg of CO2 annually — equivalent to charging 38659 smartphones.

2.58g

Carbon Footprint per page view

✗ Above sustainability target (0.50g)

Cleaner than 5% of websites

Sustainable Web Design model v4 · Page size: 9.1 MB

Your site
2.58g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.48g
Network
0.45g
End-user device
1.65g
At 10,000 monthly views: Monthly: 25.8 kg · Annual: 309.3 kg · ≈ 38659 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::
2.58g 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

2.58g

95th percentile

Cleaner than 5% of websites

✗ Above the median website

vs Median 330% more
vs Target 415% 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 141 KB (vs 9318 KB first visit). 128 of 131 resources are served from browser cache, saving 2.54g CO2 per repeat visit.
Info::
Repeat visit: 0.04g CO2 (first visit: 2.58g)
First visit
9318 KB
Repeat visit
141 KB

98% reduction on repeat visits

Saving 2.54g CO2 per returning visitor

128 resources served from cache · 3 resources re-downloaded

A+
Transfer Efficiency
98% efficient
PASS
98% efficient
Info::
Transfer efficiency: 98%
Only 217 KB of potential savings identified. Your page is well-optimized for size.
98% efficient

Total waste: 217 KB (2% of page weight)

Unused JS 217 KB

0.06g unnecessary CO2 per visit

Actual transfer 9318 KB
Theoretical minimum 9101 KB
Potential savings 217 KB (0.06g 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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