https://www.allbirds.eu
Sustainability
· 6 checks — CO2 emissions, green hosting, repeat-visit weight, carbon budget, and transfer efficiency rolled into one auditable list.SCORE
80
GRADE
B
FIX
2
REVIEW
0
PASS
4
INFO
0
Checks
64 PASS 2 FIX
DCO2 Per Page LoadAction1.33g CO2 per viewFIX
CO2 Per Page Load
Action1.33g CO2 per view
1.33g CO2 per view
Warning::
1.33g CO2 per page view
This page transfers 5.6 MB, producing an estimated 1.33g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.03g, network 0.27g, end-user device 1.02g.
Got: 1.33g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 159.0 kg CO2/year
With 10,000 page views per month, this page would generate approximately 159.0 kg of CO2 annually — equivalent to charging 19878 smartphones.
Info::
Green hosting reduces data center emissions
1.33g
Carbon Footprint per page view
✗ Above sustainability target (0.50g)
Cleaner than 30% of websites
Sustainable Web Design model v4 · Page size: 5.6 MB
Your site
1.33g
Top 10%
0.20g
Target
0.50g
Median website
0.60g
Energy Breakdown
Data center
0.03g
Network
0.27g
End-user device
1.02g
At 10,000 monthly views: Monthly: 13.3 kg · Annual: 159.0 kg · ≈ 19878 smartphone charges
DCarbon BudgetAction70th percentileFIX
Carbon Budget
Action70th percentile
70th percentile
Warning::
1.33g CO2 — above the median website (0.60g)
Heavier than an estimated 30% of websites. Reducing page weight, optimizing images, and removing unused JavaScript would lower the carbon footprint. See the Performance tab.
Info::
Estimated 70th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website
1.33g
70th percentile
Cleaner than 30% of websites
✗ Above the median website
vs Median 121% more
vs Target 165% more
A+Green HostingGreen (both)PASS
Green Hosting
Green (both)
Green (both)
Info::
Both hosting and CDN use renewable energy
Got: Hosting: Cloudflare, CDN: Cloudflare
Info::
Cloudflare: Verified by the Green Web Foundation
Info::
Cloudflare: 100% renewable energy for global network since 2019
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 Cloudflare✓CDN Cloudflare✓
Cloudflare: Verified by the Green Web Foundation
Cloudflare: 100% renewable energy for global network since 2019
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 56 KB (vs 5733 KB first visit). 195 of 197 resources are served from browser cache, saving 1.31g CO2 per repeat visit.
Info::
Repeat visit: 0.01g CO2 (first visit: 1.33g)
First visit
5733 KB
Repeat visit
56 KB
99% reduction on repeat visits
Saving 1.31g CO2 per returning visitor
195 resources served from cache · 2 resources re-downloaded
A+Transfer Efficiency96% efficientPASS
Transfer Efficiency
96% efficient
96% efficient
Info::
Transfer efficiency: 96%
Only 202 KB of potential savings identified. Your page is well-optimized for size.
Total waste: 202 KB (4% of page weight)
Unused JS 202 KB
0.05g unnecessary CO2 per visit
Actual transfer 5733 KB
Theoretical minimum 5530 KB
Potential savings 202 KB (0.05g CO2)
See Deep Analysis sections above for specific optimizations.
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: Cloudflare
All checks on this page are automated. Results are estimates - run targeted manual reviews when the score affects a release decision.