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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
3
REVIEW
2
PASS
1
INFO
0
Device:
Mobile Desktop
Checks
6
1 PASS 2 REVIEW 3 FIX
D
CO2 Per Page Load
Action
1.30g CO2 per view
FIX
1.30g CO2 per view
Warning::
1.30g CO2 per page view
This page transfers 4.6 MB, producing an estimated 1.30g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.24g, network 0.22g, end-user device 0.83g.
Got: 1.30g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 155.5 kg CO2/year
With 10,000 page views per month, this page would generate approximately 155.5 kg of CO2 annually — equivalent to charging 19435 smartphones.

1.30g

Carbon Footprint per page view

✗ Above sustainability target (0.50g)

Cleaner than 31% of websites

Sustainable Web Design model v4 · Page size: 4.6 MB

Your site
1.30g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.24g
Network
0.22g
End-user device
0.83g
At 10,000 monthly views: Monthly: 13.0 kg · Annual: 155.5 kg · ≈ 19435 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
69th percentile
FIX
69th percentile
Warning::
1.30g CO2 — above the median website (0.60g)
Heavier than an estimated 31% of websites. Reducing page weight, optimizing images, and removing unused JavaScript would lower the carbon footprint. See the Performance tab.
Info::
Estimated 69th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

1.30g

69th percentile

Cleaner than 31% of websites

✗ Above the median website

vs Median 116% more
vs Target 159% more
B
Transfer Efficiency
88% efficient
REVIEW
88% efficient
Info::
Transfer efficiency: 88%
An estimated 540 KB (12%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 540 KB of unused JavaScript. This wasted data produces 0.15g of unnecessary CO2 per page view.
88% efficient

Total waste: 540 KB (12% of page weight)

Unused JS 540 KB

0.15g unnecessary CO2 per visit

Actual transfer 4685 KB
Theoretical minimum 4144 KB
Potential savings 540 KB (0.15g 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 15 KB (vs 4685 KB first visit). 49 of 50 resources are served from browser cache, saving 1.29g CO2 per repeat visit.
Info::
Repeat visit: 0.00g CO2 (first visit: 1.30g)
First visit
4685 KB
Repeat visit
15 KB

100% reduction on repeat visits

Saving 1.29g CO2 per returning visitor

49 resources served from cache · 1 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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