https://city-data.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
0
REVIEW
3
PASS
3
INFO
0
Checks
63 PASS 3 REVIEW
BGreen HostingGreen (hosting)REVIEW
Green Hosting
Green (hosting)
Green (hosting)
Info::
OVHcloud uses renewable energy
Info::
OVHcloud: Verified by the Green Web Foundation
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 Hosting✓ Green Hosted
Hosting OVHcloud✓CDN Not identified✗
OVHcloud: Verified by the Green Web Foundation
Based on known provider commitments. Verify at thegreenwebfoundation.org
BRepeat Visit Weight60% cachedREVIEW
Repeat Visit Weight
60% cached
60% cached
Info::
60% reduction on repeat visits
Returning visitors download only 222 KB (vs 558 KB first visit). 26 of 27 resources are served from browser cache, saving 0.08g CO2 per repeat visit.
Info::
Repeat visit: 0.05g CO2 (first visit: 0.13g)
First visit
558 KB
Repeat visit
222 KB
60% reduction on repeat visits
Saving 0.08g CO2 per returning visitor
26 resources served from cache · 1 resources re-downloaded
BTransfer Efficiency89% efficientREVIEW
Transfer Efficiency
89% efficient
89% efficient
Info::
Transfer efficiency: 89%
An estimated 60 KB (11%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 60 KB of unused JavaScript. This wasted data produces 0.01g of unnecessary CO2 per page view.
Total waste: 60 KB (11% of page weight)
Unused JS 60 KB
0.01g unnecessary CO2 per visit
Actual transfer 558 KB
Theoretical minimum 498 KB
Potential savings 60 KB (0.01g CO2)
See Deep Analysis sections above for specific optimizations.
A+CO2 Per Page Load0.13g CO2 per viewPASS
CO2 Per Page Load
0.13g CO2 per view
0.13g CO2 per view
Info::
0.13g CO2 per page view
This page transfers 0.5 MB, producing an estimated 0.13g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.00g, network 0.03g, end-user device 0.10g.
Got: 0.13g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 15.5 kg CO2/year
With 10,000 page views per month, this page would generate approximately 15.5 kg of CO2 annually — equivalent to charging 1937 smartphones.
Info::
Green hosting reduces data center emissions
0.13g
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
0.13g
Top 10%
0.20g
Target
0.50g
Median website
0.60g
Energy Breakdown
Data center
0.00g
Network
0.03g
End-user device
0.10g
At 10,000 monthly views: Monthly: 1.3 kg · Annual: 15.5 kg · ≈ 1937 smartphone charges
A+Carbon Budget10th percentilePASS
Carbon Budget
10th percentile
10th percentile
Info::
0.13g 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
0.13g
10th percentile
Cleaner than 90% of websites
✓ Below the Web Sustainability Guidelines target
vs Median 78% cleaner ✓
vs Target 74% cleaner ✓
A+Green HostingWhether the site is served from green-energy infrastructurePASS
Green Hosting
Whether the site is served from green-energy infrastructure
Green Hosting
This site is hosted on green energy infrastructure
Provider: OVHcloud
All checks on this page are automated. Results are estimates - run targeted manual reviews when the score affects a release decision.