https://ala.org
Sustainability
· 6 checks — CO2 emissions, green hosting, repeat-visit weight, carbon budget, and transfer efficiency rolled into one auditable list.SCORE
87
GRADE
B
FIX
0
REVIEW
4
PASS
2
INFO
0
Checks
62 PASS 4 REVIEW
BCO2 Per Page Load0.53g CO2 per viewREVIEW
CO2 Per Page Load
0.53g CO2 per view
0.53g CO2 per view
Info::
0.53g CO2 per page view
This page transfers 2.2 MB, producing an estimated 0.53g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.01g, network 0.11g, end-user device 0.40g.
Got: 0.53g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 63.1 kg CO2/year
With 10,000 page views per month, this page would generate approximately 63.1 kg of CO2 annually — equivalent to charging 7888 smartphones.
Info::
Green hosting reduces data center emissions
0.53g
Carbon Footprint per page view
✗ Above sustainability target (0.50g)
Cleaner than 58% of websites
Sustainable Web Design model v4 · Page size: 2.2 MB
Your site
0.53g
Top 10%
0.20g
Target
0.50g
Median website
0.60g
Energy Breakdown
Data center
0.01g
Network
0.11g
End-user device
0.40g
At 10,000 monthly views: Monthly: 5.3 kg · Annual: 63.1 kg · ≈ 7888 smartphone charges
BCarbon Budget42th percentileREVIEW
Carbon Budget
42th percentile
42th percentile
Info::
0.53g CO2 — below the median website (0.60g)
Better than an estimated 58% of websites, but above the sustainability target of 0.50g. Reducing page weight would help reach the target.
Info::
Estimated 42th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website
0.53g
42nd percentile
Cleaner than 58% of websites
✗ Above the median website
vs Median 12% cleaner ✓
vs Target 5% more
BTransfer Efficiency87% efficientREVIEW
Transfer Efficiency
87% efficient
87% efficient
Info::
Transfer efficiency: 87%
An estimated 290 KB (13%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 290 KB of unused JavaScript. This wasted data produces 0.07g of unnecessary CO2 per page view.
Total waste: 290 KB (13% of page weight)
Unused JS 290 KB
0.07g unnecessary CO2 per visit
Actual transfer 2275 KB
Theoretical minimum 1984 KB
Potential savings 290 KB (0.07g CO2)
See Deep Analysis sections above for specific optimizations.
CGreen HostingActionWhether the site is served from green-energy infrastructureREVIEW
Green Hosting
ActionWhether the site is served from green-energy infrastructure
Green Hosting
No green hosting detected
AGreen HostingGreen (cdn)PASS
Green Hosting
Green (cdn)
Green (cdn)
Info::
Fastly CDN uses renewable energy
Since most traffic is served through the CDN, the majority of data transfer energy is renewable.
Info::
Fastly: 100% renewable energy for edge network
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 Pantheon✗CDN Fastly✓
Fastly: 100% renewable energy for edge network
Based on known provider commitments. Verify at thegreenwebfoundation.org
A+Repeat Visit Weight99% cachedPASS
Repeat Visit Weight
99% cached
99% cached
Info::
99% reduction on repeat visits
Returning visitors download only 32 KB (vs 2275 KB first visit). 94 of 96 resources are served from browser cache, saving 0.52g CO2 per repeat visit.
Info::
Repeat visit: 0.01g CO2 (first visit: 0.53g)
First visit
2275 KB
Repeat visit
32 KB
99% reduction on repeat visits
Saving 0.52g CO2 per returning visitor
94 resources served from cache · 2 resources re-downloaded
All checks on this page are automated. Results are estimates - run targeted manual reviews when the score affects a release decision.