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Sustainability

· 8 checks — CO2 emissions, green hosting, repeat-visit weight, carbon budget, and transfer efficiency rolled into one auditable list.
SCORE
70
GRADE
C
FIX
3
REVIEW
1
PASS
3
INFO
1
Device:
Mobile Desktop
Checks
8
3 PASS 1 REVIEW 3 FIX
D
CO2 Per Page Load
Action
1.49g CO2 per view
FIX
1.49g CO2 per view
Warning::
1.49g CO2 per page view
This page transfers 5.2 MB, producing an estimated 1.49g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.28g, network 0.26g, end-user device 0.95g.
Got: 1.49g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 178.3 kg CO2/year
With 10,000 page views per month, this page would generate approximately 178.3 kg of CO2 annually — equivalent to charging 22286 smartphones.

1.49g

Carbon Footprint per page view

✗ Above sustainability target (0.50g)

Cleaner than 25% of websites

Sustainable Web Design model v4 · Page size: 5.2 MB

Your site
1.49g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.28g
Network
0.26g
End-user device
0.95g
At 10,000 monthly views: Monthly: 14.9 kg · Annual: 178.3 kg · ≈ 22286 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::
Akamai: Committed to 50% renewable by 2030
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 Not identified✗CDN Akamai✗

Akamai: Committed to 50% renewable by 2030

Based on known provider commitments. Verify at thegreenwebfoundation.org

F
Carbon Budget
Action
75th percentile
FIX
75th percentile
Warning::
1.49g CO2 — above the median website (0.60g)
Heavier than an estimated 25% of websites. Reducing page weight, optimizing images, and removing unused JavaScript would lower the carbon footprint. See the Performance tab.
Info::
Estimated 75th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

1.49g

75th percentile

Cleaner than 25% of websites

✗ Above the median website

vs Median 148% more
vs Target 197% 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
100% cached
PASS
100% cached
Info::
100% reduction on repeat visits
Returning visitors download only 22 KB (vs 5372 KB first visit). 84 of 85 resources are served from browser cache, saving 1.48g CO2 per repeat visit.
Info::
Repeat visit: 0.01g CO2 (first visit: 1.49g)
First visit
5372 KB
Repeat visit
22 KB

100% reduction on repeat visits

Saving 1.48g CO2 per returning visitor

84 resources served from cache · 1 resources re-downloaded

A+
Transfer Efficiency
98% efficient
PASS
98% efficient
Info::
Transfer efficiency: 98%
Only 123 KB of potential savings identified. Your page is well-optimized for size.
98% efficient

Total waste: 123 KB (2% of page weight)

Unused JS 123 KB

0.03g unnecessary CO2 per visit

Actual transfer 5372 KB
Theoretical minimum 5248 KB
Potential savings 123 KB (0.03g CO2)

See Deep Analysis sections above for specific optimizations.

A+
Web Font Weight Variants
1 font weights loaded across 1 famil(y/ies) -- reasonable
PASS
1 font weights loaded across 1 famil(y/ies) -- reasonable
Info::
1 font weight(s) loaded across 1 famil(y/ies)
Image Optimization
7 images, 96 KB total, 43 KB wasted
INFO

Image Optimization Audit

Total Images

7

Total Size

96 KB

Oversized

1

Wasted

43 KB

7 missing dimensions 6 missing lazy loading
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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