https://plunketts.net
Sustainability
· 8 checks — CO2 emissions, green hosting, repeat-visit weight, carbon budget, and transfer efficiency rolled into one auditable list.SCORE
78
GRADE
C
FIX
2
REVIEW
2
PASS
3
INFO
1
Checks
83 PASS 2 REVIEW 2 FIX
DCO2 Per Page LoadAction1.07g CO2 per viewFIX
CO2 Per Page Load
Action1.07g CO2 per view
1.07g CO2 per view
Warning::
1.07g CO2 per page view
This page transfers 4.5 MB, producing an estimated 1.07g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.03g, network 0.22g, end-user device 0.82g.
Got: 1.07g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 128.1 kg CO2/year
With 10,000 page views per month, this page would generate approximately 128.1 kg of CO2 annually — equivalent to charging 16010 smartphones.
Info::
Green hosting reduces data center emissions
1.07g
Carbon Footprint per page view
✗ Above sustainability target (0.50g)
Cleaner than 37% of websites
Sustainable Web Design model v4 · Page size: 4.5 MB
Your site
1.07g
Top 10%
0.20g
Target
0.50g
Median website
0.60g
Energy Breakdown
Data center
0.03g
Network
0.22g
End-user device
0.82g
At 10,000 monthly views: Monthly: 10.7 kg · Annual: 128.1 kg · ≈ 16010 smartphone charges
DCarbon BudgetAction63th percentileFIX
Carbon Budget
Action63th percentile
63th percentile
Warning::
1.07g CO2 — above the median website (0.60g)
Heavier than an estimated 37% of websites. Reducing page weight, optimizing images, and removing unused JavaScript would lower the carbon footprint. See the Performance tab.
Info::
Estimated 63th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website
1.07g
63rd percentile
Cleaner than 37% of websites
✗ Above the median website
vs Median 78% more
vs Target 113% more
BTransfer Efficiency87% efficientREVIEW
Transfer Efficiency
87% efficient
87% efficient
Info::
Transfer efficiency: 87%
An estimated 618 KB (13%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 618 KB of unused JavaScript. This wasted data produces 0.14g of unnecessary CO2 per page view.
Total waste: 618 KB (13% of page weight)
Unused JS 618 KB
0.14g unnecessary CO2 per visit
Actual transfer 4617 KB
Theoretical minimum 3999 KB
Potential savings 618 KB (0.14g CO2)
See Deep Analysis sections above for specific optimizations.
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 Weight97% cachedPASS
Repeat Visit Weight
97% cached
97% cached
Info::
97% reduction on repeat visits
Returning visitors download only 126 KB (vs 4617 KB first visit). 214 of 220 resources are served from browser cache, saving 1.04g CO2 per repeat visit.
Info::
Repeat visit: 0.03g CO2 (first visit: 1.07g)
First visit
4617 KB
Repeat visit
126 KB
97% reduction on repeat visits
Saving 1.04g CO2 per returning visitor
214 resources served from cache · 6 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 Optimization18 images, 358 KB total, 29 KB wastedINFO
Image Optimization
18 images, 358 KB total, 29 KB wasted
Image Optimization Audit
Total Images
18
Total Size
358 KB
Oversized
2
Wasted
29 KB
9 missing alt text 10 missing dimensions 17 missing lazy loading
All checks on this page are automated. Results are estimates - run targeted manual reviews when the score affects a release decision.