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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
78
GRADE
C
FIX
1
REVIEW
2
PASS
3
INFO
0
Device:
Mobile Desktop
Checks
6
3 PASS 2 REVIEW 1 FIX
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

B
Transfer Efficiency
81% efficient
REVIEW
81% efficient
Info::
Transfer efficiency: 81%
An estimated 251 KB (19%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 251 KB of unused JavaScript. This wasted data produces 0.07g of unnecessary CO2 per page view.
81% efficient

Total waste: 251 KB (19% of page weight)

Unused JS 251 KB

0.07g unnecessary CO2 per visit

Actual transfer 1306 KB
Theoretical minimum 1054 KB
Potential savings 251 KB (0.07g 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
CO2 Per Page Load
0.36g CO2 per view
PASS
0.36g CO2 per view
Info::
0.36g CO2 per page view
This page transfers 1.3 MB, producing an estimated 0.36g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.07g, network 0.06g, end-user device 0.23g.
Got: 0.36g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 43.4 kg CO2/year
With 10,000 page views per month, this page would generate approximately 43.4 kg of CO2 annually — equivalent to charging 5420 smartphones.

0.36g

Carbon Footprint per page view

✓ Below sustainability target (0.50g)

Cleaner than 74% of websites

Sustainable Web Design model v4 · Page size: 1.3 MB

Your site
0.36g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.07g
Network
0.06g
End-user device
0.23g
At 10,000 monthly views: Monthly: 3.6 kg · Annual: 43.4 kg · ≈ 5420 smartphone charges
A+
Repeat Visit Weight
99% cached
PASS
99% cached
Info::
99% reduction on repeat visits
Returning visitors download only 12 KB (vs 1306 KB first visit). 28 of 29 resources are served from browser cache, saving 0.36g CO2 per repeat visit.
Info::
Repeat visit: 0.00g CO2 (first visit: 0.36g)
First visit
1306 KB
Repeat visit
12 KB

99% reduction on repeat visits

Saving 0.36g CO2 per returning visitor

28 resources served from cache · 1 resources re-downloaded

A
Carbon Budget
26th percentile
PASS
26th percentile
Info::
0.36g CO2 — below the sustainability target of 0.50g
Cleaner than an estimated 74% of websites analyzed. This page meets the Web Sustainability Guidelines target.
Info::
Estimated 26th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

0.36g

26th percentile

Cleaner than 74% of websites

✓ Below the Web Sustainability Guidelines target

vs Median 40% cleaner ✓
vs Target 28% cleaner ✓
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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