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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
3
REVIEW
1
PASS
2
INFO
0
Device:
Mobile Desktop
Checks
6
2 PASS 1 REVIEW 3 FIX
D
CO2 Per Page Load
Action
1.18g CO2 per view
FIX
1.18g CO2 per view
Warning::
1.18g CO2 per page view
This page transfers 4.2 MB, producing an estimated 1.18g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.22g, network 0.20g, end-user device 0.76g.
Got: 1.18g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 141.9 kg CO2/year
With 10,000 page views per month, this page would generate approximately 141.9 kg of CO2 annually — equivalent to charging 17736 smartphones.

1.18g

Carbon Footprint per page view

✗ Above sustainability target (0.50g)

Cleaner than 34% of websites

Sustainable Web Design model v4 · Page size: 4.2 MB

Your site
1.18g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.22g
Network
0.20g
End-user device
0.76g
At 10,000 monthly views: Monthly: 11.8 kg · Annual: 141.9 kg · ≈ 17736 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

D
Carbon Budget
Action
66th percentile
FIX
66th percentile
Warning::
1.18g CO2 — above the median website (0.60g)
Heavier than an estimated 34% of websites. Reducing page weight, optimizing images, and removing unused JavaScript would lower the carbon footprint. See the Performance tab.
Info::
Estimated 66th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

1.18g

66th percentile

Cleaner than 34% of websites

✗ Above the median website

vs Median 97% more
vs Target 136% 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
91% cached
PASS
91% cached
Info::
91% reduction on repeat visits
Returning visitors download only 380 KB (vs 4275 KB first visit). 59 of 61 resources are served from browser cache, saving 1.08g CO2 per repeat visit.
Info::
Repeat visit: 0.11g CO2 (first visit: 1.18g)
First visit
4275 KB
Repeat visit
380 KB

91% reduction on repeat visits

Saving 1.08g CO2 per returning visitor

59 resources served from cache · 2 resources re-downloaded

A+
Transfer Efficiency
93% efficient
PASS
93% efficient
Info::
Transfer efficiency: 93%
Only 279 KB of potential savings identified. Your page is well-optimized for size.
93% efficient

Total waste: 279 KB (7% of page weight)

Unused JS 279 KB

0.08g unnecessary CO2 per visit

Actual transfer 4275 KB
Theoretical minimum 3996 KB
Potential savings 279 KB (0.08g 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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