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https://brookings.edu

Sustainability

· 6 checks — CO2 emissions, green hosting, repeat-visit weight, carbon budget, and transfer efficiency rolled into one auditable list.
SCORE
56
GRADE
D
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
1.62g CO2 per view
FIX
1.62g CO2 per view
Warning::
1.62g CO2 per page view
This page transfers 5.7 MB, producing an estimated 1.62g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.30g, network 0.28g, end-user device 1.04g.
Got: 1.62g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 194.1 kg CO2/year
With 10,000 page views per month, this page would generate approximately 194.1 kg of CO2 annually — equivalent to charging 24268 smartphones.

1.62g

Carbon Footprint per page view

✗ Above sustainability target (0.50g)

Cleaner than 21% of websites

Sustainable Web Design model v4 · Page size: 5.7 MB

Your site
1.62g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.30g
Network
0.28g
End-user device
1.04g
At 10,000 monthly views: Monthly: 16.2 kg · Annual: 194.1 kg · ≈ 24268 smartphone charges
D
Green Hosting
Action
Not green
FIX
Not green
Info::
No confirmed renewable energy commitment detected
Consider providers like Cloudflare, Google Cloud, or Vercel that match 100% of their energy use with renewables.
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 HostingNot Green Hosted
Hosting Microsoft IIS✗CDN Not identified✗

Based on known provider commitments. Verify at thegreenwebfoundation.org

F
Carbon Budget
Action
79th percentile
FIX
79th percentile
Warning::
1.62g CO2 — above the median website (0.60g)
Heavier than an estimated 21% of websites. Reducing page weight, optimizing images, and removing unused JavaScript would lower the carbon footprint. See the Performance tab.
Info::
Estimated 79th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

1.62g

79th percentile

Cleaner than 21% of websites

✗ Above the median website

vs Median 170% more
vs Target 224% more
B
Transfer Efficiency
84% efficient
REVIEW
84% efficient
Info::
Transfer efficiency: 84%
An estimated 946 KB (16%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 946 KB of unused JavaScript. This wasted data produces 0.26g of unnecessary CO2 per page view.
84% efficient

Total waste: 946 KB (16% of page weight)

Unused JS 946 KB

0.26g unnecessary CO2 per visit

Actual transfer 5850 KB
Theoretical minimum 4903 KB
Potential savings 946 KB (0.26g 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
99% cached
PASS
99% cached
Info::
99% reduction on repeat visits
Returning visitors download only 58 KB (vs 5850 KB first visit). 88 of 90 resources are served from browser cache, saving 1.60g CO2 per repeat visit.
Info::
Repeat visit: 0.02g CO2 (first visit: 1.62g)
First visit
5850 KB
Repeat visit
58 KB

99% reduction on repeat visits

Saving 1.60g CO2 per returning visitor

88 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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