Claude Sonnet 4.6 (Adaptive Reasoning, Max Effort) vs GPT-5.6 Terra (medium)

Anthropic · OpenAI · catalog 2026-09-14

Trade-off: GPT-5.6 Terra (medium) is cheaper ($1.74 vs $2.31/M); Claude Sonnet 4.6 (Adaptive Reasoning, Max Effort) scores higher on intelligence (30.5 vs 30.4).

	Claude Sonnet 4.6 (Adaptive Reasoning, Max Effort)	GPT-5.6 Terra (medium)
Speed (tok/s)	53.6 measured	85.4 measured
Blended $/M	$2.31 derived	$1.74 derived
Intelligence index	30.5 measured	30.4 measured
TTFT (ms)	10824 measured	181 measured
Context	—	—
Coding index	63 measured	65 measured
Agentic index	33 measured	31 measured

Claude Sonnet 4.6 (Adaptive Reasoning, Max Effort) card · GPT-5.6 Terra (medium) card · 3D observatory

Verdicts use price×intelligence dominance only, and only where both sides are measured; null cells stay null with their provenance (em-dash = not in catalog). Percentile-free by design — this page compares two models, not the field. Generated page — do not hand-edit.