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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
66
GRADE
D
FIX
2
REVIEW
3
PASS
1
INFO
0
Device:
Mobile Desktop
Checks
6
1 PASS 3 REVIEW 2 FIX
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
Transfer Efficiency
Action
43% efficient
FIX
43% efficient
Critical::
Transfer efficiency: 43%
An estimated 1294 KB (57%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 1294 KB of unused JavaScript. This wasted data produces 0.36g of unnecessary CO2 per page view.
43% efficient

Total waste: 1294 KB (57% of page weight)

Unused JS 1294 KB

0.36g unnecessary CO2 per visit

Actual transfer 2287 KB
Theoretical minimum 993 KB
Potential savings 1294 KB (0.36g CO2)

See Deep Analysis sections above for specific optimizations.

B
CO2 Per Page Load
0.63g CO2 per view
REVIEW
0.63g CO2 per view
Info::
0.63g CO2 per page view
This page transfers 2.2 MB, producing an estimated 0.63g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.12g, network 0.11g, end-user device 0.41g.
Got: 0.63g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 75.9 kg CO2/year
With 10,000 page views per month, this page would generate approximately 75.9 kg of CO2 annually — equivalent to charging 9490 smartphones.

0.63g

Carbon Footprint per page view

✗ Above sustainability target (0.50g)

Cleaner than 50% of websites

Sustainable Web Design model v4 · Page size: 2.2 MB

Your site
0.63g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.12g
Network
0.11g
End-user device
0.41g
At 10,000 monthly views: Monthly: 6.3 kg · Annual: 75.9 kg · ≈ 9490 smartphone charges
B
Carbon Budget
50th percentile
REVIEW
50th percentile
Warning::
0.63g CO2 — above the median website (0.60g)
Heavier than an estimated 50% of websites. Reducing page weight, optimizing images, and removing unused JavaScript would lower the carbon footprint. See the Performance tab.
Info::
Estimated 50th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

0.63g

50th percentile

Cleaner than 50% of websites

✗ Above the median website

vs Median 5% more
vs Target 27% 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
100% cached
PASS
100% cached
Info::
100% reduction on repeat visits
Returning visitors download only 8 KB (vs 2287 KB first visit). 81 of 83 resources are served from browser cache, saving 0.63g CO2 per repeat visit.
Info::
Repeat visit: 0.00g CO2 (first visit: 0.63g)
First visit
2287 KB
Repeat visit
8 KB

100% reduction on repeat visits

Saving 0.63g CO2 per returning visitor

81 resources served from cache · 2 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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