https://rentcoolcubes.com
Sustainability
· 8 checks — CO2 emissions, green hosting, repeat-visit weight, carbon budget, and transfer efficiency rolled into one auditable list.SCORE
77
GRADE
C
FIX
2
REVIEW
2
PASS
3
INFO
1
Checks
83 PASS 2 REVIEW 2 FIX
DCO2 Per Page LoadAction1.04g CO2 per viewFIX
CO2 Per Page Load
Action1.04g CO2 per view
1.04g CO2 per view
Warning::
1.04g CO2 per page view
This page transfers 4.4 MB, producing an estimated 1.04g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.03g, network 0.21g, end-user device 0.80g.
Got: 1.04g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 124.5 kg CO2/year
With 10,000 page views per month, this page would generate approximately 124.5 kg of CO2 annually — equivalent to charging 15563 smartphones.
Info::
Green hosting reduces data center emissions
1.04g
Carbon Footprint per page view
✗ Above sustainability target (0.50g)
Cleaner than 38% of websites
Sustainable Web Design model v4 · Page size: 4.4 MB
Your site
1.04g
Top 10%
0.20g
Target
0.50g
Median website
0.60g
Energy Breakdown
Data center
0.03g
Network
0.21g
End-user device
0.80g
At 10,000 monthly views: Monthly: 10.4 kg · Annual: 124.5 kg · ≈ 15563 smartphone charges
DCarbon BudgetAction62th percentileFIX
Carbon Budget
Action62th percentile
62th percentile
Warning::
1.04g CO2 — above the median website (0.60g)
Heavier than an estimated 38% of websites. Reducing page weight, optimizing images, and removing unused JavaScript would lower the carbon footprint. See the Performance tab.
Info::
Estimated 62th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website
1.04g
62nd percentile
Cleaner than 38% of websites
✗ Above the median website
vs Median 73% more
vs Target 108% more
BTransfer Efficiency86% efficientREVIEW
Transfer Efficiency
86% efficient
86% efficient
Info::
Transfer efficiency: 86%
An estimated 639 KB (14%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 639 KB of unused JavaScript. This wasted data produces 0.15g of unnecessary CO2 per page view.
Total waste: 639 KB (14% of page weight)
Unused JS 639 KB
0.15g unnecessary CO2 per visit
Actual transfer 4488 KB
Theoretical minimum 3849 KB
Potential savings 639 KB (0.15g CO2)
See Deep Analysis sections above for specific optimizations.
BWeb Font Weight Variants6 font weights loaded across 1 famil(y/ies)REVIEW
Web Font Weight Variants
6 font weights loaded across 1 famil(y/ies)
6 font weights loaded across 1 famil(y/ies)
Info::
6 font weights loaded -- review whether all are used
5+ weights for a single page is often more than needed. Compare against the actual font-weight CSS rules in your stylesheets; trim weights that aren't applied to any element. Affected families: Inter.
A+Green HostingGreen (both)PASS
Green Hosting
Green (both)
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 Weight99% cachedPASS
Repeat Visit Weight
99% cached
99% cached
Info::
99% reduction on repeat visits
Returning visitors download only 59 KB (vs 4488 KB first visit). 182 of 185 resources are served from browser cache, saving 1.02g CO2 per repeat visit.
Info::
Repeat visit: 0.01g CO2 (first visit: 1.04g)
First visit
4488 KB
Repeat visit
59 KB
99% reduction on repeat visits
Saving 1.02g CO2 per returning visitor
182 resources served from cache · 3 resources re-downloaded
A+Green HostingWhether the site is served from green-energy infrastructurePASS
Green Hosting
Whether the site is served from green-energy infrastructure
Green Hosting
This site is hosted on green energy infrastructure
Provider: Cloudflare
Image Optimization39 images, 6484 KB total, 1483 KB wastedINFO
Image Optimization
39 images, 6484 KB total, 1483 KB wasted
Image Optimization Audit
Total Images
39
Total Size
6484 KB
Oversized
5
Wasted
1483 KB
8 missing dimensions 2 missing lazy loading
All checks on this page are automated. Results are estimates - run targeted manual reviews when the score affects a release decision.