Model Comparison
Claude Sonnet 4.5 vs o3 (Reasoning)
Claude Sonnet 4.5: Standardo3 (Reasoning): Very heavy
Side-by-side environmental impact comparison. o3 (Reasoning) uses 8.2x more energy per query.
o3 (Reasoning) uses 8.2x more energy than Claude Sonnet 4.5
21.4 Wh vs 2.6 Wh per query · 10.0 g vs 0.91 g CO₂ · 77 mL vs 5 mL water
Claude Sonnet 4.5
Anthropic
Energy per query2.6 Wh
CO₂ per query0.91 g
Water per query5 mL
VS
o3 (Reasoning)
OpenAI
Energy per query21.4 Wh
CO₂ per query10.0 g
Water per query77 mL
Claude Sonnet 4.5
ProviderAnthropic
CategoryText / Chat
Inference LocationAWS / GCP
Confidenceestimated
Efficiency TierStandard
o3 (Reasoning)
ProviderOpenAI
CategoryText / Chat
Inference LocationAzure US East / Sweden
Confidencepeer-reviewed
Efficiency TierVery heavy
Frequently Asked Questions
Which uses more energy, Claude Sonnet 4.5 or o3 (Reasoning)?
o3 (Reasoning) uses 8.2x more energy per query than Claude Sonnet 4.5. Claude Sonnet 4.5 uses 2.6 Wh per query, while o3 (Reasoning) uses 21.4 Wh.
What is the carbon footprint difference between Claude Sonnet 4.5 and o3 (Reasoning)?
o3 (Reasoning) uses 11.0x more CO₂ per query than Claude Sonnet 4.5. Claude Sonnet 4.5 emits 0.91 g of CO₂ per query compared to o3 (Reasoning)'s 10.0 g.
Which is more environmentally friendly, Claude Sonnet 4.5 or o3 (Reasoning)?
Claude Sonnet 4.5 is the more environmentally friendly option, using 2.6 Wh per query compared to o3 (Reasoning)'s 21.4 Wh. That makes o3 (Reasoning) roughly 8.2x more energy-intensive.
Calculate your footprint with these models
See how your daily usage of Claude Sonnet 4.5 and o3 (Reasoning) adds up over time. Our calculator estimates energy, carbon, and water impact.
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