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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
55
GRADE
D
FIX
3
REVIEW
2
PASS
1
INFO
0
Device:
Mobile Desktop
Checks
6
1 PASS 2 REVIEW 3 FIX
F
CO2 Per Page Load
Action
5.00g CO2 per view
FIX
5.00g CO2 per view
Critical::
5.00g CO2 per page view
This page transfers 17.7 MB, producing an estimated 5.00g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.93g, network 0.86g, end-user device 3.21g.
Got: 5.00g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 600.5 kg CO2/year
With 10,000 page views per month, this page would generate approximately 600.5 kg of CO2 annually — equivalent to charging 75059 smartphones.

5.00g

Carbon Footprint per page view

✗ Above sustainability target (0.50g)

Cleaner than 5% of websites

Sustainable Web Design model v4 · Page size: 17.7 MB

Your site
5.00g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.93g
Network
0.86g
End-user device
3.21g
At 10,000 monthly views: Monthly: 50.0 kg · Annual: 600.5 kg · ≈ 75059 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::
5.00g 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

5.00g

95th percentile

Cleaner than 5% of websites

✗ Above the median website

vs Median 734% more
vs Target 901% more
B
Transfer Efficiency
90% efficient
REVIEW
90% efficient
Info::
Transfer efficiency: 90%
An estimated 1833 KB (10%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 1833 KB of unused JavaScript. This wasted data produces 0.51g of unnecessary CO2 per page view.
90% efficient

Total waste: 1833 KB (10% of page weight)

Unused JS 1833 KB

0.51g unnecessary CO2 per visit

Actual transfer 18093 KB
Theoretical minimum 16260 KB
Potential savings 1833 KB (0.51g 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
100% cached
PASS
100% cached
Info::
100% reduction on repeat visits
Returning visitors download only 86 KB (vs 18093 KB first visit). 250 of 260 resources are served from browser cache, saving 4.98g CO2 per repeat visit.
Info::
Repeat visit: 0.02g CO2 (first visit: 5.00g)
First visit
18093 KB
Repeat visit
86 KB

100% reduction on repeat visits

Saving 4.98g CO2 per returning visitor

250 resources served from cache · 10 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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