https://poste.it
Sustainability
· 8 checks — CO2 emissions, green hosting, repeat-visit weight, carbon budget, and transfer efficiency rolled into one auditable list.SCORE
71
GRADE
C
FIX
3
REVIEW
2
PASS
2
INFO
1
Checks
82 PASS 2 REVIEW 3 FIX
DCO2 Per Page LoadAction1.01g CO2 per viewFIX
CO2 Per Page Load
Action1.01g CO2 per view
1.01g CO2 per view
Warning::
1.01g CO2 per page view
This page transfers 3.6 MB, producing an estimated 1.01g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.19g, network 0.18g, end-user device 0.65g.
Got: 1.01g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 121.6 kg CO2/year
With 10,000 page views per month, this page would generate approximately 121.6 kg of CO2 annually — equivalent to charging 15201 smartphones.
1.01g
Carbon Footprint per page view
✗ Above sustainability target (0.50g)
Cleaner than 39% of websites
Sustainable Web Design model v4 · Page size: 3.6 MB
Your site
1.01g
Top 10%
0.20g
Target
0.50g
Median website
0.60g
Energy Breakdown
Data center
0.19g
Network
0.18g
End-user device
0.65g
At 10,000 monthly views: Monthly: 10.1 kg · Annual: 121.6 kg · ≈ 15201 smartphone charges
DGreen HostingActionNot greenFIX
Green Hosting
ActionNot green
Not green
Info::
No confirmed renewable energy commitment detected
Consider providers like Cloudflare, Google Cloud, or Vercel that match 100% of their energy use with renewables.
Info::
Azure: Microsoft is carbon-negative; Azure renewable varies by region
Info::
Azure CDN: Inherits Azure 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 HostingNot Green Hosted
Hosting Azure✗CDN Azure CDN✗
Azure: Microsoft is carbon-negative; Azure renewable varies by region
Azure CDN: Inherits Azure regional renewable mix
Based on known provider commitments. Verify at thegreenwebfoundation.org
DCarbon BudgetAction61th percentileFIX
Carbon Budget
Action61th percentile
61th percentile
Warning::
1.01g 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
1.01g
61st percentile
Cleaner than 39% of websites
✗ Above the median website
vs Median 69% more
vs Target 103% more
BWeb Font Weight VariantsNo detectable Google Fonts weightsREVIEW
Web Font Weight Variants
No detectable Google Fonts weights
No detectable Google Fonts weights
Info::
No detectable Google Fonts weights
The analyzer detects font weights via Google Fonts URL parameters (~70% of font-using sites). Self-hosted fonts and non-Google CDN fonts aren't visible to URL-based detection. If you self-host fonts, manually audit how many @font-face weights you ship -- 2-3 weights per family is typically enough; 5+ is usually unused payload.
CGreen HostingActionWhether the site is served from green-energy infrastructureREVIEW
Green Hosting
ActionWhether the site is served from green-energy infrastructure
Green Hosting
No green hosting detected
A+Repeat Visit Weight99% cachedPASS
Repeat Visit Weight
99% cached
99% cached
Info::
99% reduction on repeat visits
Returning visitors download only 35 KB (vs 3664 KB first visit). 108 of 110 resources are served from browser cache, saving 1.00g CO2 per repeat visit.
Info::
Repeat visit: 0.01g CO2 (first visit: 1.01g)
First visit
3664 KB
Repeat visit
35 KB
99% reduction on repeat visits
Saving 1.00g CO2 per returning visitor
108 resources served from cache · 2 resources re-downloaded
A+Transfer Efficiency98% efficientPASS
Transfer Efficiency
98% efficient
98% efficient
Info::
Transfer efficiency: 98%
Only 67 KB of potential savings identified. Your page is well-optimized for size.
Total waste: 67 KB (2% of page weight)
Unused JS 67 KB
0.02g unnecessary CO2 per visit
Actual transfer 3664 KB
Theoretical minimum 3596 KB
Potential savings 67 KB (0.02g CO2)
See Deep Analysis sections above for specific optimizations.
Image Optimization34 images, 11 KB total, 4 KB wastedINFO
Image Optimization
34 images, 11 KB total, 4 KB wasted
Image Optimization Audit
Total Images
34
Total Size
11 KB
Oversized
1
Wasted
4 KB
1 missing alt text 34 missing dimensions 1 missing lazy loading
All checks on this page are automated. Results are estimates - run targeted manual reviews when the score affects a release decision.