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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
60
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
2.03g CO2 per view
FIX
2.03g CO2 per view
Critical::
2.03g CO2 per page view
This page transfers 7.2 MB, producing an estimated 2.03g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.38g, network 0.35g, end-user device 1.31g.
Got: 2.03g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 244.2 kg CO2/year
With 10,000 page views per month, this page would generate approximately 244.2 kg of CO2 annually — equivalent to charging 30520 smartphones.

2.03g

Carbon Footprint per page view

✗ Above sustainability target (0.50g)

Cleaner than 5% of websites

Sustainable Web Design model v4 · Page size: 7.2 MB

Your site
2.03g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.38g
Network
0.35g
End-user device
1.31g
At 10,000 monthly views: Monthly: 20.3 kg · Annual: 244.2 kg · ≈ 30520 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::
AWS: Renewable energy varies by region; committed to 100% by 2025
Info::
AWS CloudFront: Renewable varies by edge location
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 AWS✗CDN AWS CloudFront✗

AWS: Renewable energy varies by region; committed to 100% by 2025

AWS CloudFront: Renewable varies by edge location

Based on known provider commitments. Verify at thegreenwebfoundation.org

F
Carbon Budget
Action
95th percentile
FIX
95th percentile
Warning::
2.03g CO2 — above the median website (0.60g)
Heavier than an estimated 5% of websites. Reducing page weight, optimizing images, and removing unused JavaScript would lower the carbon footprint. See the Performance tab.
Info::
Estimated 95th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

2.03g

95th percentile

Cleaner than 5% of websites

✗ Above the median website

vs Median 239% more
vs Target 307% more
B
Transfer Efficiency
81% efficient
REVIEW
81% efficient
Info::
Transfer efficiency: 81%
An estimated 1393 KB (19%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 1393 KB of unused JavaScript. This wasted data produces 0.39g of unnecessary CO2 per page view.
81% efficient

Total waste: 1393 KB (19% of page weight)

Unused JS 1393 KB

0.39g unnecessary CO2 per visit

Actual transfer 7357 KB
Theoretical minimum 5963 KB
Potential savings 1393 KB (0.39g 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
98% cached
PASS
98% cached
Info::
98% reduction on repeat visits
Returning visitors download only 130 KB (vs 7357 KB first visit). 196 of 208 resources are served from browser cache, saving 2.00g CO2 per repeat visit.
Info::
Repeat visit: 0.04g CO2 (first visit: 2.03g)
First visit
7357 KB
Repeat visit
130 KB

98% reduction on repeat visits

Saving 2.00g CO2 per returning visitor

196 resources served from cache · 12 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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