https://www.rss.org
Sustainability
· 8 checks — CO2 emissions, green hosting, repeat-visit weight, carbon budget, and transfer efficiency rolled into one auditable list.SCORE
81
GRADE
B
FIX
2
REVIEW
1
PASS
4
INFO
1
Checks
84 PASS 1 REVIEW 2 FIX
DCO2 Per Page LoadAction1.10g CO2 per viewFIX
CO2 Per Page Load
Action1.10g CO2 per view
1.10g CO2 per view
Warning::
1.10g CO2 per page view
This page transfers 4.6 MB, producing an estimated 1.10g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.03g, network 0.23g, end-user device 0.84g.
Got: 1.10g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 131.6 kg CO2/year
With 10,000 page views per month, this page would generate approximately 131.6 kg of CO2 annually — equivalent to charging 16454 smartphones.
Info::
Green hosting reduces data center emissions
1.10g
Carbon Footprint per page view
✗ Above sustainability target (0.50g)
Cleaner than 36% of websites
Sustainable Web Design model v4 · Page size: 4.6 MB
Your site
1.10g
Top 10%
0.20g
Target
0.50g
Median website
0.60g
Energy Breakdown
Data center
0.03g
Network
0.23g
End-user device
0.84g
At 10,000 monthly views: Monthly: 11.0 kg · Annual: 131.6 kg · ≈ 16454 smartphone charges
DCarbon BudgetAction64th percentileFIX
Carbon Budget
Action64th percentile
64th percentile
Warning::
1.10g CO2 — above the median website (0.60g)
Heavier than an estimated 36% of websites. Reducing page weight, optimizing images, and removing unused JavaScript would lower the carbon footprint. See the Performance tab.
Info::
Estimated 64th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website
1.10g
64th percentile
Cleaner than 36% of websites
✗ Above the median website
vs Median 83% more
vs Target 119% 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.
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 60 KB (vs 4745 KB first visit). 58 of 59 resources are served from browser cache, saving 1.08g CO2 per repeat visit.
Info::
Repeat visit: 0.01g CO2 (first visit: 1.10g)
First visit
4745 KB
Repeat visit
60 KB
99% reduction on repeat visits
Saving 1.08g CO2 per returning visitor
58 resources served from cache · 1 resources re-downloaded
A+Transfer Efficiency97% efficientPASS
Transfer Efficiency
97% efficient
97% efficient
Info::
Transfer efficiency: 97%
Only 160 KB of potential savings identified. Your page is well-optimized for size.
Total waste: 160 KB (3% of page weight)
Unused JS 160 KB
0.04g unnecessary CO2 per visit
Actual transfer 4745 KB
Theoretical minimum 4585 KB
Potential savings 160 KB (0.04g CO2)
See Deep Analysis sections above for specific optimizations.
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 Optimization18 images, 9229 KB total, 0 KB wastedINFO
Image Optimization
18 images, 9229 KB total, 0 KB wasted
Image Optimization Audit
Total Images
18
Total Size
9229 KB
18 missing dimensions 7 missing lazy loading
All checks on this page are automated. Results are estimates - run targeted manual reviews when the score affects a release decision.