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https://cars.com

Sustainability

· 6 checks — CO2 emissions, green hosting, repeat-visit weight, carbon budget, and transfer efficiency rolled into one auditable list.
SCORE
66
GRADE
D
FIX
3
REVIEW
2
PASS
1
INFO
0
Device:
Mobile Desktop
Checks
6
1 PASS 2 REVIEW 3 FIX
F
CO2 Per Page Load
Action
1.54g CO2 per view
FIX
1.54g CO2 per view
Warning::
1.54g CO2 per page view
This page transfers 5.4 MB, producing an estimated 1.54g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.29g, network 0.27g, end-user device 0.99g.
Got: 1.54g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 185.0 kg CO2/year
With 10,000 page views per month, this page would generate approximately 185.0 kg of CO2 annually — equivalent to charging 23130 smartphones.

1.54g

Carbon Footprint per page view

✗ Above sustainability target (0.50g)

Cleaner than 24% of websites

Sustainable Web Design model v4 · Page size: 5.4 MB

Your site
1.54g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.29g
Network
0.27g
End-user device
0.99g
At 10,000 monthly views: Monthly: 15.4 kg · Annual: 185.0 kg · ≈ 23130 smartphone charges
D
Green Hosting
Action
Unknown
FIX
Unknown
Info::
Hosting provider could not be identified
Without knowing the provider, we cannot determine their energy sourcing. Check with your hosting provider about their renewable energy commitments.
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 HostingUnable to Determine
Hosting Not identified✗CDN Not identified✗

Based on known provider commitments. Verify at thegreenwebfoundation.org

F
Carbon Budget
Action
76th percentile
FIX
76th percentile
Warning::
1.54g CO2 — above the median website (0.60g)
Heavier than an estimated 24% of websites. Reducing page weight, optimizing images, and removing unused JavaScript would lower the carbon footprint. See the Performance tab.
Info::
Estimated 76th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

1.54g

76th percentile

Cleaner than 24% of websites

✗ Above the median website

vs Median 157% more
vs Target 208% more
B
Transfer Efficiency
81% efficient
REVIEW
81% efficient
Info::
Transfer efficiency: 81%
An estimated 1068 KB (19%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 1068 KB of unused JavaScript. This wasted data produces 0.30g of unnecessary CO2 per page view.
81% efficient

Total waste: 1068 KB (19% of page weight)

Unused JS 1068 KB

0.30g unnecessary CO2 per visit

Actual transfer 5575 KB
Theoretical minimum 4506 KB
Potential savings 1068 KB (0.30g CO2)

See Deep Analysis sections above for specific optimizations.

C
Green Hosting
Action
Whether the site is served from green-energy infrastructure
REVIEW

Green Hosting

No green hosting detected

A+
Repeat Visit Weight
97% cached
PASS
97% cached
Info::
97% reduction on repeat visits
Returning visitors download only 168 KB (vs 5575 KB first visit). 500 of 520 resources are served from browser cache, saving 1.50g CO2 per repeat visit.
Info::
Repeat visit: 0.05g CO2 (first visit: 1.54g)
First visit
5575 KB
Repeat visit
168 KB

97% reduction on repeat visits

Saving 1.50g CO2 per returning visitor

500 resources served from cache · 20 resources re-downloaded

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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