https://www.theguardian.com
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
1
REVIEW
3
PASS
3
INFO
1
Checks
83 PASS 3 REVIEW 1 FIX
DGreen HostingActionUnknownFIX
Green Hosting
ActionUnknown
Unknown
Info::
Hosting provider could not be identified
Without knowing the provider, we cannot determine their energy sourcing. Check with your hosting provider about their renewable energy commitments.
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 HostingUnable to Determine
Hosting Not identified✗CDN Not identified✗
Based on known provider commitments. Verify at thegreenwebfoundation.org
BTransfer Efficiency78% efficientREVIEW
Transfer Efficiency
78% efficient
78% efficient
Info::
Transfer efficiency: 78%
An estimated 238 KB (22%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 238 KB of unused JavaScript. This wasted data produces 0.07g of unnecessary CO2 per page view.
Total waste: 238 KB (22% of page weight)
Unused JS 238 KB
0.07g unnecessary CO2 per visit
Actual transfer 1082 KB
Theoretical minimum 844 KB
Potential savings 238 KB (0.07g 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.
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
ACO2 Per Page Load0.30g CO2 per viewPASS
CO2 Per Page Load
0.30g CO2 per view
0.30g CO2 per view
Info::
0.30g CO2 per page view
This page transfers 1.1 MB, producing an estimated 0.30g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.06g, network 0.05g, end-user device 0.19g.
Got: 0.30g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 35.9 kg CO2/year
With 10,000 page views per month, this page would generate approximately 35.9 kg of CO2 annually — equivalent to charging 4490 smartphones.
0.30g
Carbon Footprint per page view
✓ Below sustainability target (0.50g)
Cleaner than 81% of websites
Sustainable Web Design model v4 · Page size: 1.1 MB
Your site
0.30g
Top 10%
0.20g
Target
0.50g
Median website
0.60g
Energy Breakdown
Data center
0.06g
Network
0.05g
End-user device
0.19g
At 10,000 monthly views: Monthly: 3.0 kg · Annual: 35.9 kg · ≈ 4490 smartphone charges
A+Repeat Visit Weight87% cachedPASS
Repeat Visit Weight
87% cached
87% cached
Info::
87% reduction on repeat visits
Returning visitors download only 145 KB (vs 1082 KB first visit). 103 of 105 resources are served from browser cache, saving 0.26g CO2 per repeat visit.
Info::
Repeat visit: 0.04g CO2 (first visit: 0.30g)
First visit
1082 KB
Repeat visit
145 KB
87% reduction on repeat visits
Saving 0.26g CO2 per returning visitor
103 resources served from cache · 2 resources re-downloaded
ACarbon Budget19th percentilePASS
Carbon Budget
19th percentile
19th percentile
Info::
0.30g CO2 — below the sustainability target of 0.50g
Cleaner than an estimated 81% of websites analyzed. This page meets the Web Sustainability Guidelines target.
Info::
Estimated 19th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website
0.30g
19th percentile
Cleaner than 81% of websites
✓ Below the Web Sustainability Guidelines target
vs Median 50% cleaner ✓
vs Target 40% cleaner ✓
Image Optimization114 images, 92 KB total, 0 KB wastedINFO
Image Optimization
114 images, 92 KB total, 0 KB wasted
Image Optimization Audit
Total Images
114
Total Size
92 KB
Oversized
1
2 missing alt text 113 missing dimensions 12 missing lazy loading
All checks on this page are automated. Results are estimates - run targeted manual reviews when the score affects a release decision.