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https://rubiconproject.com

Sustainability

· 6 checks — CO2 emissions, green hosting, repeat-visit weight, carbon budget, and transfer efficiency rolled into one auditable list.
SCORE
88
GRADE
B
FIX
1
REVIEW
1
PASS
4
INFO
0
Device:
Mobile Desktop
Checks
6
4 PASS 1 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::
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 Apache HTTP Server✗CDN Not identified✗

Based on known provider commitments. Verify at thegreenwebfoundation.org

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
0.15g CO2 per view
PASS
0.15g CO2 per view
Info::
0.15g CO2 per page view
This page transfers 0.5 MB, producing an estimated 0.15g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.03g, network 0.03g, end-user device 0.09g.
Got: 0.15g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 17.4 kg CO2/year
With 10,000 page views per month, this page would generate approximately 17.4 kg of CO2 annually — equivalent to charging 2175 smartphones.

0.15g

Carbon Footprint per page view

✓ Below sustainability target (0.50g)

Cleaner than 90% of websites

Sustainable Web Design model v4 · Page size: 0.5 MB

Your site
0.15g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.03g
Network
0.03g
End-user device
0.09g
At 10,000 monthly views: Monthly: 1.5 kg · Annual: 17.4 kg · ≈ 2175 smartphone charges
A+
Repeat Visit Weight
81% cached
PASS
81% cached
Info::
81% reduction on repeat visits
Returning visitors download only 100 KB (vs 524 KB first visit). 22 of 24 resources are served from browser cache, saving 0.12g CO2 per repeat visit.
Info::
Repeat visit: 0.03g CO2 (first visit: 0.15g)
First visit
524 KB
Repeat visit
100 KB

81% reduction on repeat visits

Saving 0.12g CO2 per returning visitor

22 resources served from cache · 2 resources re-downloaded

A+
Carbon Budget
10th percentile
PASS
10th percentile
Info::
0.15g CO2 — below the sustainability target of 0.50g
Cleaner than an estimated 90% of websites analyzed. This page meets the Web Sustainability Guidelines target.
Info::
Estimated 10th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

0.15g

10th percentile

Cleaner than 90% of websites

✓ Below the Web Sustainability Guidelines target

vs Median 76% cleaner ✓
vs Target 71% cleaner ✓
A+
Transfer Efficiency
100% efficient
PASS
100% efficient
Info::
Transfer efficiency: 100%
Only 0 KB of potential savings identified. Your page is well-optimized for size.
100% efficient
Actual transfer 524 KB
Theoretical minimum 524 KB

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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