https://metamask.io
Sustainability
· 6 checks — CO2 emissions, green hosting, repeat-visit weight, carbon budget, and transfer efficiency rolled into one auditable list.SCORE
76
GRADE
C
FIX
2
REVIEW
1
PASS
3
INFO
0
Checks
63 PASS 1 REVIEW 2 FIX
DCO2 Per Page LoadAction0.89g CO2 per viewFIX
CO2 Per Page Load
Action0.89g CO2 per view
0.89g CO2 per view
Info::
0.89g CO2 per page view
This page transfers 3.8 MB, producing an estimated 0.89g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.02g, network 0.18g, end-user device 0.68g.
Got: 0.89g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 106.7 kg CO2/year
With 10,000 page views per month, this page would generate approximately 106.7 kg of CO2 annually — equivalent to charging 13338 smartphones.
Info::
Green hosting reduces data center emissions
0.89g
Carbon Footprint per page view
✗ Above sustainability target (0.50g)
Cleaner than 42% of websites
Sustainable Web Design model v4 · Page size: 3.8 MB
Your site
0.89g
Top 10%
0.20g
Target
0.50g
Median website
0.60g
Energy Breakdown
Data center
0.02g
Network
0.18g
End-user device
0.68g
At 10,000 monthly views: Monthly: 8.9 kg · Annual: 106.7 kg · ≈ 13338 smartphone charges
DCarbon BudgetAction58th percentileFIX
Carbon Budget
Action58th percentile
58th percentile
Warning::
0.89g CO2 — above the median website (0.60g)
Heavier than an estimated 42% of websites. Reducing page weight, optimizing images, and removing unused JavaScript would lower the carbon footprint. See the Performance tab.
Info::
Estimated 58th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website
0.89g
58th percentile
Cleaner than 42% of websites
✗ Above the median website
vs Median 48% more
vs Target 78% more
BTransfer Efficiency85% efficientREVIEW
Transfer Efficiency
85% efficient
85% efficient
Info::
Transfer efficiency: 85%
An estimated 567 KB (15%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 567 KB of unused JavaScript. This wasted data produces 0.13g of unnecessary CO2 per page view.
Total waste: 567 KB (15% of page weight)
Unused JS 567 KB
0.13g unnecessary CO2 per visit
Actual transfer 3847 KB
Theoretical minimum 3279 KB
Potential savings 567 KB (0.13g CO2)
See Deep Analysis sections above for specific optimizations.
A+Green HostingGreen (both)PASS
Green Hosting
Green (both)
Green (both)
Info::
Both hosting and CDN use renewable energy
Got: Hosting: Next.js, CDN: Cloudflare
Info::
Next.js: 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 Next.js✓CDN Cloudflare✓
Next.js: 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 Weight98% cachedPASS
Repeat Visit Weight
98% cached
98% cached
Info::
98% reduction on repeat visits
Returning visitors download only 66 KB (vs 3847 KB first visit). 87 of 88 resources are served from browser cache, saving 0.87g CO2 per repeat visit.
Info::
Repeat visit: 0.02g CO2 (first visit: 0.89g)
First visit
3847 KB
Repeat visit
66 KB
98% reduction on repeat visits
Saving 0.87g CO2 per returning visitor
87 resources served from cache · 1 resources re-downloaded
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.