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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
62
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
1.64g CO2 per view
FIX
1.64g CO2 per view
Warning::
1.64g CO2 per page view
This page transfers 5.8 MB, producing an estimated 1.64g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.30g, network 0.28g, end-user device 1.05g.
Got: 1.64g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 196.4 kg CO2/year
With 10,000 page views per month, this page would generate approximately 196.4 kg of CO2 annually — equivalent to charging 24552 smartphones.

1.64g

Carbon Footprint per page view

✗ Above sustainability target (0.50g)

Cleaner than 21% of websites

Sustainable Web Design model v4 · Page size: 5.8 MB

Your site
1.64g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.30g
Network
0.28g
End-user device
1.05g
At 10,000 monthly views: Monthly: 16.4 kg · Annual: 196.4 kg · ≈ 24552 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
79th percentile
FIX
79th percentile
Warning::
1.64g CO2 — above the median website (0.60g)
Heavier than an estimated 21% of websites. Reducing page weight, optimizing images, and removing unused JavaScript would lower the carbon footprint. See the Performance tab.
Info::
Estimated 79th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

1.64g

79th percentile

Cleaner than 21% of websites

✗ Above the median website

vs Median 173% more
vs Target 227% 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
99% cached
PASS
99% cached
Info::
99% reduction on repeat visits
Returning visitors download only 50 KB (vs 5918 KB first visit). 166 of 170 resources are served from browser cache, saving 1.62g CO2 per repeat visit.
Info::
Repeat visit: 0.01g CO2 (first visit: 1.64g)
First visit
5918 KB
Repeat visit
50 KB

99% reduction on repeat visits

Saving 1.62g CO2 per returning visitor

166 resources served from cache · 4 resources re-downloaded

A+
Transfer Efficiency
91% efficient
PASS
91% efficient
Info::
Transfer efficiency: 91%
Only 542 KB of potential savings identified. Your page is well-optimized for size.
91% efficient

Total waste: 542 KB (9% of page weight)

Unused JS 542 KB

0.15g unnecessary CO2 per visit

Actual transfer 5918 KB
Theoretical minimum 5375 KB
Potential savings 542 KB (0.15g 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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