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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
65
GRADE
D
FIX
3
REVIEW
1
PASS
2
INFO
0
Checks
6
2 PASS 1 REVIEW 3 FIX
D
CO2 Per Page Load
Action
1.13g CO2 per view
FIX
1.13g CO2 per view
Warning::
1.13g CO2 per page view
This page transfers 4.8 MB, producing an estimated 1.13g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.03g, network 0.23g, end-user device 0.87g.
Got: 1.13g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 135.2 kg CO2/year
With 10,000 page views per month, this page would generate approximately 135.2 kg of CO2 annually — equivalent to charging 16901 smartphones.
Info::
Green hosting reduces data center emissions

1.13g

Carbon Footprint per page view

Above sustainability target (0.50g)

Cleaner than 35% of websites

Sustainable Web Design model v4 · Page size: 4.8 MB

Your site
1.13g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.03g
Network
0.23g
End-user device
0.87g
At 10,000 monthly views: Monthly: 11.3 kg · Annual: 135.2 kg · ≈ 16901 smartphone charges
D
Carbon Budget
Action
65th percentile
FIX
65th percentile
Warning::
1.13g CO2 — above the median website (0.60g)
Heavier than an estimated 35% of websites. Reducing page weight, optimizing images, and removing unused JavaScript would lower the carbon footprint. See the Performance tab.
Info::
Estimated 65th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

1.13g

65th percentile

Cleaner than 35% of websites

Above the median website

vs Median 88% more
vs Target 125% more
D
Transfer Efficiency
Action
48% efficient
FIX
48% efficient
Critical::
Transfer efficiency: 48%
An estimated 2550 KB (52%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 2550 KB of unused JavaScript. This wasted data produces 0.59g of unnecessary CO2 per page view.
48% efficient

Total waste: 2550 KB (52% of page weight)

Unused JS 2550 KB

0.59g unnecessary CO2 per visit

Actual transfer 4874 KB
Theoretical minimum 2323 KB
Potential savings 2550 KB (0.59g 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
Green Hosting
Green (cdn)
PASS
Green (cdn)
Info::
Cloudflare CDN uses renewable energy
Since most traffic is served through the CDN, the majority of data transfer energy is renewable.
Info::
Cloudflare: 100% renewable energy for global network since 2019
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 Hosting Green Hosted
Hosting Not identifiedCDN Cloudflare

Cloudflare: 100% renewable energy for global network since 2019

Based on known provider commitments. Verify at thegreenwebfoundation.org

A+
Repeat Visit Weight
99% cached
PASS
99% cached
Info::
99% reduction on repeat visits
Returning visitors download only 29 KB (vs 4874 KB first visit). 129 of 130 resources are served from browser cache, saving 1.12g CO2 per repeat visit.
Info::
Repeat visit: 0.01g CO2 (first visit: 1.13g)
First visit
4874 KB
Repeat visit
29 KB

99% reduction on repeat visits

Saving 1.12g CO2 per returning visitor

129 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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