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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
72
GRADE
C
FIX
2
REVIEW
0
PASS
4
INFO
0
Device:
Mobile Desktop
Checks
6
4 PASS 2 FIX
F
CO2 Per Page Load
Action
1.83g CO2 per view
FIX
1.83g CO2 per view
Warning::
1.83g CO2 per page view
This page transfers 7.7 MB, producing an estimated 1.83g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.05g, network 0.38g, end-user device 1.41g.
Got: 1.83g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 220.0 kg CO2/year
With 10,000 page views per month, this page would generate approximately 220.0 kg of CO2 annually — equivalent to charging 27504 smartphones.
Info::
Green hosting reduces data center emissions

1.83g

Carbon Footprint per page view

✗ Above sustainability target (0.50g)

Cleaner than 15% of websites

Sustainable Web Design model v4 · Page size: 7.7 MB

Your site
1.83g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.05g
Network
0.38g
End-user device
1.41g
At 10,000 monthly views: Monthly: 18.3 kg · Annual: 220.0 kg · ≈ 27504 smartphone charges
F
Carbon Budget
Action
85th percentile
FIX
85th percentile
Warning::
1.83g CO2 — above the median website (0.60g)
Heavier than an estimated 15% of websites. Reducing page weight, optimizing images, and removing unused JavaScript would lower the carbon footprint. See the Performance tab.
Info::
Estimated 85th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

1.83g

85th percentile

Cleaner than 15% of websites

✗ Above the median website

vs Median 206% more
vs Target 267% more
A+
Green Hosting
Green (both)
PASS
Green (both)
Info::
Both hosting and CDN use renewable energy
Got: Hosting: Pantheon, CDN: Cloudflare
Info::
Pantheon: Verified by the Green Web Foundation
Info::
Cloudflare: 100% renewable energy for global network since 2019
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 Cloudflare✓

Pantheon: Verified by the Green Web Foundation

Cloudflare: 100% renewable energy for global network since 2019

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 37 KB (vs 7933 KB first visit). 115 of 116 resources are served from browser cache, saving 1.83g CO2 per repeat visit.
Info::
Repeat visit: 0.01g CO2 (first visit: 1.83g)
First visit
7933 KB
Repeat visit
37 KB

100% reduction on repeat visits

Saving 1.83g CO2 per returning visitor

115 resources served from cache · 1 resources re-downloaded

A+
Transfer Efficiency
96% efficient
PASS
96% efficient
Info::
Transfer efficiency: 96%
Only 311 KB of potential savings identified. Your page is well-optimized for size.
96% efficient

Total waste: 311 KB (4% of page weight)

Unused JS 311 KB

0.07g unnecessary CO2 per visit

Actual transfer 7933 KB
Theoretical minimum 7621 KB
Potential savings 311 KB (0.07g CO2)

See Deep Analysis sections above for specific optimizations.

A+
Green Hosting
Whether the site is served from green-energy infrastructure
PASS

Green Hosting

This site is hosted on green energy infrastructure

Provider: Cloudflare

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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