https://hackernoon.com
Sustainability
· 8 checks — CO2 emissions, green hosting, repeat-visit weight, carbon budget, and transfer efficiency rolled into one auditable list.SCORE
65
GRADE
D
FIX
2
REVIEW
2
PASS
3
INFO
1
Checks
83 PASS 2 REVIEW 2 FIX
FCO2 Per Page LoadAction2.49g CO2 per viewFIX
CO2 Per Page Load
Action2.49g CO2 per view
2.49g CO2 per view
Critical::
2.49g CO2 per page view
This page transfers 10.5 MB, producing an estimated 2.49g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.06g, network 0.51g, end-user device 1.91g.
Got: 2.49g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 298.3 kg CO2/year
With 10,000 page views per month, this page would generate approximately 298.3 kg of CO2 annually — equivalent to charging 37290 smartphones.
Info::
Green hosting reduces data center emissions
2.49g
Carbon Footprint per page view
✗ Above sustainability target (0.50g)
Cleaner than 5% of websites
Sustainable Web Design model v4 · Page size: 10.5 MB
Your site
2.49g
Top 10%
0.20g
Target
0.50g
Median website
0.60g
Energy Breakdown
Data center
0.06g
Network
0.51g
End-user device
1.91g
At 10,000 monthly views: Monthly: 24.9 kg · Annual: 298.3 kg · ≈ 37290 smartphone charges
FCarbon BudgetAction95th percentileFIX
Carbon Budget
Action95th percentile
95th percentile
Warning::
2.49g CO2 — above the median website (0.60g)
Heavier than an estimated 5% of websites. Reducing page weight, optimizing images, and removing unused JavaScript would lower the carbon footprint. See the Performance tab.
Info::
Estimated 95th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website
2.49g
95th percentile
Cleaner than 5% of websites
✗ Above the median website
vs Median 314% more
vs Target 397% more
BTransfer Efficiency87% efficientREVIEW
Transfer Efficiency
87% efficient
87% efficient
Info::
Transfer efficiency: 87%
An estimated 1395 KB (13%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 1395 KB of unused JavaScript. This wasted data produces 0.32g of unnecessary CO2 per page view.
Total waste: 1395 KB (13% of page weight)
Unused JS 1395 KB
0.32g unnecessary CO2 per visit
Actual transfer 10755 KB
Theoretical minimum 9359 KB
Potential savings 1395 KB (0.32g CO2)
See Deep Analysis sections above for specific optimizations.
CWeb Font Weight VariantsAction11 font weights loaded across 4 famil(y/ies)REVIEW
Web Font Weight Variants
Action11 font weights loaded across 4 famil(y/ies)
11 font weights loaded across 4 famil(y/ies)
Warning::
11 font weights loaded -- likely 100+ KB of unused payload
Loading 11 font weights typically transfers 200-400 KB just for fonts. Most pages legitimately use 2-3 weights (regular + bold, maybe medium). Audit which weights your stylesheet actually applies and trim the Google Fonts URL accordingly. Affected families: IBM Plex Mono, IBM Plex Sans, Inter, Source Code Pro.
A+Green HostingGreen (both)PASS
Green Hosting
Green (both)
Green (both)
Info::
Both hosting and CDN use renewable energy
Got: Hosting: Next.js, CDN: Cloudflare
Info::
Next.js: 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 Next.js✓CDN Cloudflare✓
Next.js: 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 Weight100% cachedPASS
Repeat Visit Weight
100% cached
100% cached
Info::
100% reduction on repeat visits
Returning visitors download only 42 KB (vs 10755 KB first visit). 216 of 217 resources are served from browser cache, saving 2.48g CO2 per repeat visit.
Info::
Repeat visit: 0.01g CO2 (first visit: 2.49g)
First visit
10755 KB
Repeat visit
42 KB
100% reduction on repeat visits
Saving 2.48g CO2 per returning visitor
216 resources served from cache · 1 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 Optimization92 images, 190 KB total, 150 KB wastedINFO
Image Optimization
92 images, 190 KB total, 150 KB wasted
Image Optimization Audit
Total Images
92
Total Size
190 KB
Oversized
6
Wasted
150 KB
43 missing dimensions 6 missing lazy loading
All checks on this page are automated. Results are estimates - run targeted manual reviews when the score affects a release decision.