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https://tidd.ly

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
2
PASS
2
INFO
0
Device:
Mobile Desktop
Checks
6
2 PASS 2 REVIEW 2 FIX
D
CO2 Per Page Load
Action
0.99g CO2 per view
FIX
0.99g CO2 per view
Info::
0.99g CO2 per page view
This page transfers 4.2 MB, producing an estimated 0.99g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.02g, network 0.21g, end-user device 0.76g.
Got: 0.99g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 119.3 kg CO2/year
With 10,000 page views per month, this page would generate approximately 119.3 kg of CO2 annually — equivalent to charging 14908 smartphones.
Info::
Green hosting reduces data center emissions

0.99g

Carbon Footprint per page view

✗ Above sustainability target (0.50g)

Cleaner than 39% of websites

Sustainable Web Design model v4 · Page size: 4.2 MB

Your site
0.99g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.02g
Network
0.21g
End-user device
0.76g
At 10,000 monthly views: Monthly: 9.9 kg · Annual: 119.3 kg · ≈ 14908 smartphone charges
D
Carbon Budget
Action
61th percentile
FIX
61th percentile
Warning::
0.99g CO2 — above the median website (0.60g)
Heavier than an estimated 39% of websites. Reducing page weight, optimizing images, and removing unused JavaScript would lower the carbon footprint. See the Performance tab.
Info::
Estimated 61th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

0.99g

61st percentile

Cleaner than 39% of websites

✗ Above the median website

vs Median 66% more
vs Target 99% more
B
Green Hosting
Green (hosting)
REVIEW
Green (hosting)
Info::
Google Cloud uses renewable energy
Info::
Google Cloud: Verified by the Green Web Foundation
Info::
Google Cloud CDN: Inherits Google Cloud regional renewable mix
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 Google Cloud✓CDN Google Cloud CDN✗

Google Cloud: Verified by the Green Web Foundation

Google Cloud CDN: Inherits Google Cloud regional renewable mix

Based on known provider commitments. Verify at thegreenwebfoundation.org

B
Transfer Efficiency
83% efficient
REVIEW
83% efficient
Info::
Transfer efficiency: 83%
An estimated 748 KB (17%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 748 KB of unused JavaScript. This wasted data produces 0.17g of unnecessary CO2 per page view.
83% efficient

Total waste: 748 KB (17% of page weight)

Unused JS 748 KB

0.17g unnecessary CO2 per visit

Actual transfer 4300 KB
Theoretical minimum 3552 KB
Potential savings 748 KB (0.17g CO2)

See Deep Analysis sections above for specific optimizations.

A+
Repeat Visit Weight
98% cached
PASS
98% cached
Info::
98% reduction on repeat visits
Returning visitors download only 96 KB (vs 4300 KB first visit). 98 of 100 resources are served from browser cache, saving 0.97g CO2 per repeat visit.
Info::
Repeat visit: 0.02g CO2 (first visit: 0.99g)
First visit
4300 KB
Repeat visit
96 KB

98% reduction on repeat visits

Saving 0.97g CO2 per returning visitor

98 resources served from cache · 2 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: Google Cloud

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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