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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
76
GRADE
C
FIX
2
REVIEW
1
PASS
3
INFO
0
Device:
Mobile Desktop
Checks
6
3 PASS 1 REVIEW 2 FIX
D
CO2 Per Page Load
Action
0.91g CO2 per view
FIX
0.91g CO2 per view
Info::
0.91g CO2 per page view
This page transfers 3.8 MB, producing an estimated 0.91g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.02g, network 0.19g, end-user device 0.70g.
Got: 0.91g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 108.7 kg CO2/year
With 10,000 page views per month, this page would generate approximately 108.7 kg of CO2 annually — equivalent to charging 13589 smartphones.
Info::
Green hosting reduces data center emissions

0.91g

Carbon Footprint per page view

✗ Above sustainability target (0.50g)

Cleaner than 42% of websites

Sustainable Web Design model v4 · Page size: 3.8 MB

Your site
0.91g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.02g
Network
0.19g
End-user device
0.70g
At 10,000 monthly views: Monthly: 9.1 kg · Annual: 108.7 kg · ≈ 13589 smartphone charges
D
Carbon Budget
Action
58th percentile
FIX
58th percentile
Warning::
0.91g CO2 — above the median website (0.60g)
Heavier than an estimated 42% of websites. Reducing page weight, optimizing images, and removing unused JavaScript would lower the carbon footprint. See the Performance tab.
Info::
Estimated 58th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

0.91g

58th percentile

Cleaner than 42% of websites

✗ Above the median website

vs Median 51% more
vs Target 81% more
C
Transfer Efficiency
Action
66% efficient
REVIEW
66% efficient
Warning::
Transfer efficiency: 66%
An estimated 1322 KB (34%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 1322 KB of unused JavaScript. This wasted data produces 0.31g of unnecessary CO2 per page view.
66% efficient

Total waste: 1322 KB (34% of page weight)

Unused JS 1322 KB

0.31g unnecessary CO2 per visit

Actual transfer 3919 KB
Theoretical minimum 2596 KB
Potential savings 1322 KB (0.31g CO2)

See Deep Analysis sections above for specific optimizations.

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
98% cached
PASS
98% cached
Info::
98% reduction on repeat visits
Returning visitors download only 82 KB (vs 3919 KB first visit). 142 of 146 resources are served from browser cache, saving 0.89g CO2 per repeat visit.
Info::
Repeat visit: 0.02g CO2 (first visit: 0.91g)
First visit
3919 KB
Repeat visit
82 KB

98% reduction on repeat visits

Saving 0.89g CO2 per returning visitor

142 resources served from cache · 4 resources re-downloaded

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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