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Sustainability

· 6 checks — CO2 emissions, green hosting, repeat-visit weight, carbon budget, and transfer efficiency rolled into one auditable list.
SCORE
69
GRADE
D
FIX
2
REVIEW
1
PASS
3
INFO
0
Device:
Mobile Desktop
Checks
6
3 PASS 1 REVIEW 2 FIX
F
CO2 Per Page Load
Action
1.68g CO2 per view
FIX
1.68g CO2 per view
Warning::
1.68g CO2 per page view
This page transfers 7.1 MB, producing an estimated 1.68g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.04g, network 0.35g, end-user device 1.29g.
Got: 1.68g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 202.2 kg CO2/year
With 10,000 page views per month, this page would generate approximately 202.2 kg of CO2 annually — equivalent to charging 25269 smartphones.
Info::
Green hosting reduces data center emissions

1.68g

Carbon Footprint per page view

✗ Above sustainability target (0.50g)

Cleaner than 20% of websites

Sustainable Web Design model v4 · Page size: 7.1 MB

Your site
1.68g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.04g
Network
0.35g
End-user device
1.29g
At 10,000 monthly views: Monthly: 16.8 kg · Annual: 202.2 kg · ≈ 25269 smartphone charges
F
Carbon Budget
Action
80th percentile
FIX
80th percentile
Warning::
1.68g CO2 — above the median website (0.60g)
Heavier than an estimated 20% of websites. Reducing page weight, optimizing images, and removing unused JavaScript would lower the carbon footprint. See the Performance tab.
Info::
Estimated 80th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

1.68g

80th percentile

Cleaner than 20% of websites

✗ Above the median website

vs Median 181% more
vs Target 237% more
C
Green Hosting
Action
Whether the site is served from green-energy infrastructure
REVIEW

Green Hosting

No green hosting detected

A
Green Hosting
Green (cdn)
PASS
Green (cdn)
Info::
Fastly CDN uses renewable energy
Since most traffic is served through the CDN, the majority of data transfer energy is renewable.
Info::
Fastly: 100% renewable energy for edge network
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 Pantheon✗CDN Fastly✓

Fastly: 100% renewable energy for edge network

Based on known provider commitments. Verify at thegreenwebfoundation.org

A+
Repeat Visit Weight
100% cached
PASS
100% cached
Info::
100% reduction on repeat visits
Returning visitors download only 35 KB (vs 7288 KB first visit). 87 of 88 resources are served from browser cache, saving 1.68g CO2 per repeat visit.
Info::
Repeat visit: 0.01g CO2 (first visit: 1.68g)
First visit
7288 KB
Repeat visit
35 KB

100% reduction on repeat visits

Saving 1.68g CO2 per returning visitor

87 resources served from cache · 1 resources re-downloaded

A+
Transfer Efficiency
94% efficient
PASS
94% efficient
Info::
Transfer efficiency: 94%
Only 432 KB of potential savings identified. Your page is well-optimized for size.
94% efficient

Total waste: 432 KB (6% of page weight)

Unused JS 432 KB

0.10g unnecessary CO2 per visit

Actual transfer 7288 KB
Theoretical minimum 6855 KB
Potential savings 432 KB (0.10g 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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