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https://swarthmore.edu

Sustainability

· 6 checks — CO2 emissions, green hosting, repeat-visit weight, carbon budget, and transfer efficiency rolled into one auditable list.
SCORE
59
GRADE
D
FIX
3
REVIEW
1
PASS
2
INFO
0
Device:
Mobile Desktop
Checks
6
2 PASS 1 REVIEW 3 FIX
F
CO2 Per Page Load
Action
5.25g CO2 per view
FIX
5.25g CO2 per view
Critical::
5.25g CO2 per page view
This page transfers 18.6 MB, producing an estimated 5.25g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.97g, network 0.91g, end-user device 3.37g.
Got: 5.25g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 630.4 kg CO2/year
With 10,000 page views per month, this page would generate approximately 630.4 kg of CO2 annually — equivalent to charging 78805 smartphones.

5.25g

Carbon Footprint per page view

✗ Above sustainability target (0.50g)

Cleaner than 5% of websites

Sustainable Web Design model v4 · Page size: 18.6 MB

Your site
5.25g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.97g
Network
0.91g
End-user device
3.37g
At 10,000 monthly views: Monthly: 52.5 kg · Annual: 630.4 kg · ≈ 78805 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
95th percentile
FIX
95th percentile
Warning::
5.25g CO2 — above the median website (0.60g)
Heavier than an estimated 5% of websites. Reducing page weight, optimizing images, and removing unused JavaScript would lower the carbon footprint. See the Performance tab.
Info::
Estimated 95th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

5.25g

95th percentile

Cleaner than 5% of websites

✗ Above the median website

vs Median 776% more
vs Target 951% 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
100% cached
PASS
100% cached
Info::
100% reduction on repeat visits
Returning visitors download only 94 KB (vs 18996 KB first visit). 58 of 61 resources are served from browser cache, saving 5.23g CO2 per repeat visit.
Info::
Repeat visit: 0.03g CO2 (first visit: 5.25g)
First visit
18996 KB
Repeat visit
94 KB

100% reduction on repeat visits

Saving 5.23g CO2 per returning visitor

58 resources served from cache · 3 resources re-downloaded

A+
Transfer Efficiency
99% efficient
PASS
99% efficient
Info::
Transfer efficiency: 99%
Only 208 KB of potential savings identified. Your page is well-optimized for size.
99% efficient

Total waste: 208 KB (1% of page weight)

Unused JS 208 KB

0.06g unnecessary CO2 per visit

Actual transfer 18996 KB
Theoretical minimum 18788 KB
Potential savings 208 KB (0.06g 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.

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