Skip to content
https://as.com

Sustainability

· 6 checks — CO2 emissions, green hosting, repeat-visit weight, carbon budget, and transfer efficiency rolled into one auditable list.
SCORE
70
GRADE
C
FIX
3
REVIEW
1
PASS
2
INFO
0
Device:
Mobile Desktop
Checks
6
2 PASS 1 REVIEW 3 FIX
D
CO2 Per Page Load
Action
1.20g CO2 per view
FIX
1.20g CO2 per view
Warning::
1.20g CO2 per page view
This page transfers 4.2 MB, producing an estimated 1.20g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.22g, network 0.21g, end-user device 0.77g.
Got: 1.20g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 144.3 kg CO2/year
With 10,000 page views per month, this page would generate approximately 144.3 kg of CO2 annually — equivalent to charging 18031 smartphones.

1.20g

Carbon Footprint per page view

✗ Above sustainability target (0.50g)

Cleaner than 33% of websites

Sustainable Web Design model v4 · Page size: 4.2 MB

Your site
1.20g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.22g
Network
0.21g
End-user device
0.77g
At 10,000 monthly views: Monthly: 12.0 kg · Annual: 144.3 kg · ≈ 18031 smartphone charges
D
Green Hosting
Action
Unknown
FIX
Unknown
Info::
Hosting provider could not be identified
Without knowing the provider, we cannot determine their energy sourcing. Check with your hosting provider about their renewable energy commitments.
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 HostingUnable to Determine
Hosting Not identified✗CDN Not identified✗

Based on known provider commitments. Verify at thegreenwebfoundation.org

D
Carbon Budget
Action
67th percentile
FIX
67th percentile
Warning::
1.20g CO2 — above the median website (0.60g)
Heavier than an estimated 33% of websites. Reducing page weight, optimizing images, and removing unused JavaScript would lower the carbon footprint. See the Performance tab.
Info::
Estimated 67th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

1.20g

67th percentile

Cleaner than 33% of websites

✗ Above the median website

vs Median 100% more
vs Target 140% more
C
Green Hosting
Action
Whether the site is served from green-energy infrastructure
REVIEW

Green Hosting

No green hosting detected

A+
Repeat Visit Weight
96% cached
PASS
96% cached
Info::
96% reduction on repeat visits
Returning visitors download only 156 KB (vs 4346 KB first visit). 258 of 262 resources are served from browser cache, saving 1.16g CO2 per repeat visit.
Info::
Repeat visit: 0.04g CO2 (first visit: 1.20g)
First visit
4346 KB
Repeat visit
156 KB

96% reduction on repeat visits

Saving 1.16g CO2 per returning visitor

258 resources served from cache · 4 resources re-downloaded

A+
Transfer Efficiency
96% efficient
PASS
96% efficient
Info::
Transfer efficiency: 96%
Only 193 KB of potential savings identified. Your page is well-optimized for size.
96% efficient

Total waste: 193 KB (4% of page weight)

Unused JS 193 KB

0.05g unnecessary CO2 per visit

Actual transfer 4346 KB
Theoretical minimum 4153 KB
Potential savings 193 KB (0.05g CO2)

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.

Send Feedback