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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
54
GRADE
F
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
1.85g CO2 per view
FIX
1.85g CO2 per view
Warning::
1.85g CO2 per page view
This page transfers 6.5 MB, producing an estimated 1.85g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.34g, network 0.32g, end-user device 1.19g.
Got: 1.85g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 221.6 kg CO2/year
With 10,000 page views per month, this page would generate approximately 221.6 kg of CO2 annually — equivalent to charging 27699 smartphones.

1.85g

Carbon Footprint per page view

✗ Above sustainability target (0.50g)

Cleaner than 15% of websites

Sustainable Web Design model v4 · Page size: 6.5 MB

Your site
1.85g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.34g
Network
0.32g
End-user device
1.19g
At 10,000 monthly views: Monthly: 18.5 kg · Annual: 221.6 kg · ≈ 27699 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
85th percentile
FIX
85th percentile
Warning::
1.85g CO2 — above the median website (0.60g)
Heavier than an estimated 15% of websites. Reducing page weight, optimizing images, and removing unused JavaScript would lower the carbon footprint. See the Performance tab.
Info::
Estimated 85th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

1.85g

85th percentile

Cleaner than 15% of websites

✗ Above the median website

vs Median 208% more
vs Target 269% more
C
Transfer Efficiency
Action
63% efficient
REVIEW
63% efficient
Warning::
Transfer efficiency: 63%
An estimated 2456 KB (37%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 2456 KB of unused JavaScript. This wasted data produces 0.68g of unnecessary CO2 per page view.
63% efficient

Total waste: 2456 KB (37% of page weight)

Unused JS 2456 KB

0.68g unnecessary CO2 per visit

Actual transfer 6677 KB
Theoretical minimum 4220 KB
Potential savings 2456 KB (0.68g 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
96% cached
PASS
96% cached
Info::
96% reduction on repeat visits
Returning visitors download only 294 KB (vs 6677 KB first visit). 177 of 180 resources are served from browser cache, saving 1.77g CO2 per repeat visit.
Info::
Repeat visit: 0.08g CO2 (first visit: 1.85g)
First visit
6677 KB
Repeat visit
294 KB

96% reduction on repeat visits

Saving 1.77g CO2 per returning visitor

177 resources served from cache · 3 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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