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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
61
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
2.06g CO2 per view
FIX
2.06g CO2 per view
Critical::
2.06g CO2 per page view
This page transfers 8.7 MB, producing an estimated 2.06g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.05g, network 0.43g, end-user device 1.58g.
Got: 2.06g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 247.5 kg CO2/year
With 10,000 page views per month, this page would generate approximately 247.5 kg of CO2 annually — equivalent to charging 30939 smartphones.
Info::
Green hosting reduces data center emissions

2.06g

Carbon Footprint per page view

✗ Above sustainability target (0.50g)

Cleaner than 5% of websites

Sustainable Web Design model v4 · Page size: 8.7 MB

Your site
2.06g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.05g
Network
0.43g
End-user device
1.58g
At 10,000 monthly views: Monthly: 20.6 kg · Annual: 247.5 kg · ≈ 30939 smartphone charges
F
Carbon Budget
Action
95th percentile
FIX
95th percentile
Warning::
2.06g 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

2.06g

95th percentile

Cleaner than 5% of websites

✗ Above the median website

vs Median 244% more
vs Target 313% more
C
Transfer Efficiency
Action
70% efficient
REVIEW
70% efficient
Warning::
Transfer efficiency: 70%
An estimated 2645 KB (30%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 2645 KB of unused JavaScript. This wasted data produces 0.61g of unnecessary CO2 per page view.
70% efficient

Total waste: 2645 KB (30% of page weight)

Unused JS 2645 KB

0.61g unnecessary CO2 per visit

Actual transfer 8923 KB
Theoretical minimum 6278 KB
Potential savings 2645 KB (0.61g 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: Cloudflare, CDN: Cloudflare
Info::
Cloudflare: 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 Cloudflare✓CDN Cloudflare✓

Cloudflare: 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
97% cached
PASS
97% cached
Info::
97% reduction on repeat visits
Returning visitors download only 286 KB (vs 8923 KB first visit). 172 of 182 resources are served from browser cache, saving 2.00g CO2 per repeat visit.
Info::
Repeat visit: 0.07g CO2 (first visit: 2.06g)
First visit
8923 KB
Repeat visit
286 KB

97% reduction on repeat visits

Saving 2.00g CO2 per returning visitor

172 resources served from cache · 10 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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