Skip to content
https://si.com

Sustainability

· 6 checks — CO2 emissions, green hosting, repeat-visit weight, carbon budget, and transfer efficiency rolled into one auditable list.
SCORE
55
GRADE
D
FIX
3
REVIEW
2
PASS
1
INFO
0
Device:
Mobile Desktop
Checks
6
1 PASS 2 REVIEW 3 FIX
F
CO2 Per Page Load
Action
1.59g CO2 per view
FIX
1.59g CO2 per view
Warning::
1.59g CO2 per page view
This page transfers 5.6 MB, producing an estimated 1.59g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.29g, network 0.28g, end-user device 1.02g.
Got: 1.59g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 191.0 kg CO2/year
With 10,000 page views per month, this page would generate approximately 191.0 kg of CO2 annually — equivalent to charging 23877 smartphones.

1.59g

Carbon Footprint per page view

✗ Above sustainability target (0.50g)

Cleaner than 22% of websites

Sustainable Web Design model v4 · Page size: 5.6 MB

Your site
1.59g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.29g
Network
0.28g
End-user device
1.02g
At 10,000 monthly views: Monthly: 15.9 kg · Annual: 191.0 kg · ≈ 23877 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

F
Carbon Budget
Action
78th percentile
FIX
78th percentile
Warning::
1.59g CO2 — above the median website (0.60g)
Heavier than an estimated 22% of websites. Reducing page weight, optimizing images, and removing unused JavaScript would lower the carbon footprint. See the Performance tab.
Info::
Estimated 78th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

1.59g

78th percentile

Cleaner than 22% of websites

✗ Above the median website

vs Median 165% more
vs Target 218% more
B
Transfer Efficiency
84% efficient
REVIEW
84% efficient
Info::
Transfer efficiency: 84%
An estimated 901 KB (16%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 901 KB of unused JavaScript. This wasted data produces 0.25g of unnecessary CO2 per page view.
84% efficient

Total waste: 901 KB (16% of page weight)

Unused JS 901 KB

0.25g unnecessary CO2 per visit

Actual transfer 5755 KB
Theoretical minimum 4853 KB
Potential savings 901 KB (0.25g CO2)

See Deep Analysis sections above for specific optimizations.

C
Green Hosting
Action
Whether the site is served from green-energy infrastructure
REVIEW

Green Hosting

No green hosting detected

A+
Repeat Visit Weight
94% cached
PASS
94% cached
Info::
94% reduction on repeat visits
Returning visitors download only 330 KB (vs 5755 KB first visit). 467 of 469 resources are served from browser cache, saving 1.50g CO2 per repeat visit.
Info::
Repeat visit: 0.09g CO2 (first visit: 1.59g)
First visit
5755 KB
Repeat visit
330 KB

94% reduction on repeat visits

Saving 1.50g CO2 per returning visitor

467 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.

Send Feedback