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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
73
GRADE
C
FIX
2
REVIEW
2
PASS
2
INFO
0
Device:
Mobile Desktop
Checks
6
2 PASS 2 REVIEW 2 FIX
F
CO2 Per Page Load
Action
1.67g CO2 per view
FIX
1.67g CO2 per view
Warning::
1.67g CO2 per page view
This page transfers 7.1 MB, producing an estimated 1.67g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.04g, network 0.35g, end-user device 1.28g.
Got: 1.67g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 200.7 kg CO2/year
With 10,000 page views per month, this page would generate approximately 200.7 kg of CO2 annually — equivalent to charging 25090 smartphones.
Info::
Green hosting reduces data center emissions

1.67g

Carbon Footprint per page view

✗ Above sustainability target (0.50g)

Cleaner than 20% of websites

Sustainable Web Design model v4 · Page size: 7.1 MB

Your site
1.67g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.04g
Network
0.35g
End-user device
1.28g
At 10,000 monthly views: Monthly: 16.7 kg · Annual: 200.7 kg · ≈ 25090 smartphone charges
F
Carbon Budget
Action
80th percentile
FIX
80th percentile
Warning::
1.67g CO2 — above the median website (0.60g)
Heavier than an estimated 20% of websites. Reducing page weight, optimizing images, and removing unused JavaScript would lower the carbon footprint. See the Performance tab.
Info::
Estimated 80th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

1.67g

80th percentile

Cleaner than 20% of websites

✗ Above the median website

vs Median 179% more
vs Target 235% more
B
Transfer Efficiency
84% efficient
REVIEW
84% efficient
Info::
Transfer efficiency: 84%
An estimated 1161 KB (16%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 1161 KB of unused JavaScript. This wasted data produces 0.27g of unnecessary CO2 per page view.
84% efficient

Total waste: 1161 KB (16% of page weight)

Unused JS 1161 KB

0.27g unnecessary CO2 per visit

Actual transfer 7236 KB
Theoretical minimum 6075 KB
Potential savings 1161 KB (0.27g 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::
Azure: Microsoft is carbon-negative; Azure renewable varies by region
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 Azure✗CDN Cloudflare✓

Azure: Microsoft is carbon-negative; Azure renewable varies by region

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 105 KB (vs 7236 KB first visit). 237 of 243 resources are served from browser cache, saving 1.65g CO2 per repeat visit.
Info::
Repeat visit: 0.02g CO2 (first visit: 1.67g)
First visit
7236 KB
Repeat visit
105 KB

99% reduction on repeat visits

Saving 1.65g CO2 per returning visitor

237 resources served from cache · 6 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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