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https://allaboutbirds.org

Sustainability

· 6 checks — CO2 emissions, green hosting, repeat-visit weight, carbon budget, and transfer efficiency rolled into one auditable list.
SCORE
68
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
1.89g CO2 per view
FIX
1.89g CO2 per view
Warning::
1.89g CO2 per page view
This page transfers 8.0 MB, producing an estimated 1.89g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.05g, network 0.39g, end-user device 1.45g.
Got: 1.89g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 226.8 kg CO2/year
With 10,000 page views per month, this page would generate approximately 226.8 kg of CO2 annually — equivalent to charging 28347 smartphones.
Info::
Green hosting reduces data center emissions

1.89g

Carbon Footprint per page view

✗ Above sustainability target (0.50g)

Cleaner than 14% of websites

Sustainable Web Design model v4 · Page size: 8.0 MB

Your site
1.89g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.05g
Network
0.39g
End-user device
1.45g
At 10,000 monthly views: Monthly: 18.9 kg · Annual: 226.8 kg · ≈ 28347 smartphone charges
F
Carbon Budget
Action
86th percentile
FIX
86th percentile
Warning::
1.89g CO2 — above the median website (0.60g)
Heavier than an estimated 14% of websites. Reducing page weight, optimizing images, and removing unused JavaScript would lower the carbon footprint. See the Performance tab.
Info::
Estimated 86th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

1.89g

86th percentile

Cleaner than 14% of websites

✗ Above the median website

vs Median 215% more
vs Target 278% more
B
Transfer Efficiency
88% efficient
REVIEW
88% efficient
Info::
Transfer efficiency: 88%
An estimated 942 KB (12%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 942 KB of unused JavaScript. This wasted data produces 0.22g of unnecessary CO2 per page view.
88% efficient

Total waste: 942 KB (12% of page weight)

Unused JS 942 KB

0.22g unnecessary CO2 per visit

Actual transfer 8176 KB
Theoretical minimum 7233 KB
Potential savings 942 KB (0.22g 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
100% cached
PASS
100% cached
Info::
100% reduction on repeat visits
Returning visitors download only 36 KB (vs 8176 KB first visit). 214 of 219 resources are served from browser cache, saving 1.88g CO2 per repeat visit.
Info::
Repeat visit: 0.01g CO2 (first visit: 1.89g)
First visit
8176 KB
Repeat visit
36 KB

100% reduction on repeat visits

Saving 1.88g CO2 per returning visitor

214 resources served from cache · 5 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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