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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
56
GRADE
D
FIX
3
REVIEW
1
PASS
2
INFO
0
Device:
Mobile Desktop
Checks
6
2 PASS 1 REVIEW 3 FIX
F
CO2 Per Page Load
Action
4.00g CO2 per view
FIX
4.00g CO2 per view
Critical::
4.00g CO2 per page view
This page transfers 14.1 MB, producing an estimated 4.00g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.74g, network 0.69g, end-user device 2.56g.
Got: 4.00g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 479.4 kg CO2/year
With 10,000 page views per month, this page would generate approximately 479.4 kg of CO2 annually — equivalent to charging 59929 smartphones.

4.00g

Carbon Footprint per page view

✗ Above sustainability target (0.50g)

Cleaner than 5% of websites

Sustainable Web Design model v4 · Page size: 14.1 MB

Your site
4.00g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.74g
Network
0.69g
End-user device
2.56g
At 10,000 monthly views: Monthly: 40.0 kg · Annual: 479.4 kg · ≈ 59929 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 Amazon Web Services✗CDN Not identified✗

Based on known provider commitments. Verify at thegreenwebfoundation.org

F
Carbon Budget
Action
95th percentile
FIX
95th percentile
Warning::
4.00g 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

4.00g

95th percentile

Cleaner than 5% of websites

✗ Above the median website

vs Median 566% more
vs Target 699% more
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 124 KB (vs 14446 KB first visit). 348 of 358 resources are served from browser cache, saving 3.96g CO2 per repeat visit.
Info::
Repeat visit: 0.03g CO2 (first visit: 4.00g)
First visit
14446 KB
Repeat visit
124 KB

99% reduction on repeat visits

Saving 3.96g CO2 per returning visitor

348 resources served from cache · 10 resources re-downloaded

A+
Transfer Efficiency
93% efficient
PASS
93% efficient
Info::
Transfer efficiency: 93%
Only 1070 KB of potential savings identified. Your page is well-optimized for size.
93% efficient

Total waste: 1070 KB (7% of page weight)

Unused JS 1070 KB

0.30g unnecessary CO2 per visit

Actual transfer 14446 KB
Theoretical minimum 13376 KB
Potential savings 1070 KB (0.30g CO2)

See Deep Analysis sections above for specific optimizations.

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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