Skip to content
https://rsna.org

Sustainability

· 6 checks — CO2 emissions, green hosting, repeat-visit weight, carbon budget, and transfer efficiency rolled into one auditable list.
SCORE
66
GRADE
D
FIX
3
REVIEW
1
PASS
2
INFO
0
Checks
6
2 PASS 1 REVIEW 3 FIX
D
CO2 Per Page Load
Action
1.40g CO2 per view
FIX
1.40g CO2 per view
Warning::
1.40g CO2 per page view
This page transfers 4.9 MB, producing an estimated 1.40g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.26g, network 0.24g, end-user device 0.90g.
Got: 1.40g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 167.4 kg CO2/year
With 10,000 page views per month, this page would generate approximately 167.4 kg of CO2 annually — equivalent to charging 20926 smartphones.

1.40g

Carbon Footprint per page view

Above sustainability target (0.50g)

Cleaner than 28% of websites

Sustainable Web Design model v4 · Page size: 4.9 MB

Your site
1.40g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.26g
Network
0.24g
End-user device
0.90g
At 10,000 monthly views: Monthly: 14.0 kg · Annual: 167.4 kg · ≈ 20926 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 identifiedCDN Not identified

Based on known provider commitments. Verify at thegreenwebfoundation.org

F
Carbon Budget
Action
72th percentile
FIX
72th percentile
Warning::
1.40g CO2 — above the median website (0.60g)
Heavier than an estimated 28% of websites. Reducing page weight, optimizing images, and removing unused JavaScript would lower the carbon footprint. See the Performance tab.
Info::
Estimated 72th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

1.40g

72nd percentile

Cleaner than 28% of websites

Above the median website

vs Median 133% more
vs Target 179% 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
99% cached
PASS
99% cached
Info::
99% reduction on repeat visits
Returning visitors download only 25 KB (vs 5044 KB first visit). 82 of 84 resources are served from browser cache, saving 1.39g CO2 per repeat visit.
Info::
Repeat visit: 0.01g CO2 (first visit: 1.40g)
First visit
5044 KB
Repeat visit
25 KB

99% reduction on repeat visits

Saving 1.39g CO2 per returning visitor

82 resources served from cache · 2 resources re-downloaded

A+
Transfer Efficiency
98% efficient
PASS
98% efficient
Info::
Transfer efficiency: 98%
Only 93 KB of potential savings identified. Your page is well-optimized for size.
98% efficient

Total waste: 93 KB (2% of page weight)

Unused JS 93 KB

0.03g unnecessary CO2 per visit

Actual transfer 5044 KB
Theoretical minimum 4950 KB
Potential savings 93 KB (0.03g 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