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https://www.compositebonding.london

Sustainability

· 8 checks — CO2 emissions, green hosting, repeat-visit weight, carbon budget, and transfer efficiency rolled into one auditable list.
SCORE
86
GRADE
B
FIX
0
REVIEW
2
PASS
5
INFO
1
Checks
8
5 PASS 2 REVIEW
B
Green Hosting
Green (hosting)
REVIEW
Green (hosting)
Info::
Hetzner Online GmbH uses renewable energy
Info::
Hetzner Online GmbH: Verified by the Green Web Foundation
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 Hetzner Online GmbH✓CDN Not identified✗

Hetzner Online GmbH: Verified by the Green Web Foundation

Based on known provider commitments. Verify at thegreenwebfoundation.org

C
Web Font Weight Variants
Action
12 font weights loaded across 3 famil(y/ies)
REVIEW
12 font weights loaded across 3 famil(y/ies)
Warning::
12 font weights loaded -- likely 100+ KB of unused payload
Loading 12 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: Montserrat, Oswald, Poppins.
A
CO2 Per Page Load
0.31g CO2 per view
PASS
0.31g CO2 per view
Info::
0.31g CO2 per page view
This page transfers 1.3 MB, producing an estimated 0.31g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.01g, network 0.06g, end-user device 0.24g.
Got: 0.31g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 37.2 kg CO2/year
With 10,000 page views per month, this page would generate approximately 37.2 kg of CO2 annually — equivalent to charging 4656 smartphones.
Info::
Green hosting reduces data center emissions

0.31g

Carbon Footprint per page view

✓ Below sustainability target (0.50g)

Cleaner than 79% of websites

Sustainable Web Design model v4 · Page size: 1.3 MB

Your site
0.31g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.01g
Network
0.06g
End-user device
0.24g
At 10,000 monthly views: Monthly: 3.1 kg · Annual: 37.2 kg · ≈ 4656 smartphone charges
A+
Repeat Visit Weight
99% cached
PASS
99% cached
Info::
99% reduction on repeat visits
Returning visitors download only 7 KB (vs 1342 KB first visit). 58 of 59 resources are served from browser cache, saving 0.31g CO2 per repeat visit.
Info::
Repeat visit: 0.00g CO2 (first visit: 0.31g)
First visit
1342 KB
Repeat visit
7 KB

99% reduction on repeat visits

Saving 0.31g CO2 per returning visitor

58 resources served from cache · 1 resources re-downloaded

A
Carbon Budget
21th percentile
PASS
21th percentile
Info::
0.31g CO2 — below the sustainability target of 0.50g
Cleaner than an estimated 79% of websites analyzed. This page meets the Web Sustainability Guidelines target.
Info::
Estimated 21th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

0.31g

21st percentile

Cleaner than 79% of websites

✓ Below the Web Sustainability Guidelines target

vs Median 48% cleaner ✓
vs Target 38% cleaner ✓
A+
Transfer Efficiency
90% efficient
PASS
90% efficient
Info::
Transfer efficiency: 90%
Only 132 KB of potential savings identified. Your page is well-optimized for size.
90% efficient

Total waste: 132 KB (10% of page weight)

Unused JS 132 KB

0.03g unnecessary CO2 per visit

Actual transfer 1342 KB
Theoretical minimum 1210 KB
Potential savings 132 KB (0.03g CO2)

See Deep Analysis sections above for specific optimizations.

A+
Green Hosting
Whether the site is served from green-energy infrastructure
PASS

Green Hosting

This site is hosted on green energy infrastructure

Provider: Hetzner Online GmbH

Image Optimization
17 images, 521 KB total, 61 KB wasted
INFO

Image Optimization Audit

Total Images

17

Total Size

521 KB

Oversized

2

Wasted

61 KB

17 missing dimensions 13 missing lazy loading
All checks on this page are automated. Results are estimates - run targeted manual reviews when the score affects a release decision.

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