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Claude Sonnet 5 vs GPT-5.6 Luna Pro

Side-by-side API pricing and Artificial Analysis performance for Claude Sonnet 5 (Anthropic) and GPT-5.6 Luna Pro (OpenAI). Green cells mark the better value in each row.

Prices updated Sep 16, 2026, 8:26 AM UTC · refreshed hourly

Claude Sonnet 5

Anthropic

GPT-5.6 Luna Pro

OpenAI

Pricing
Input $/1M$2.00$0.20
Output $/1M$10.00$1.20
Blended $/1M (3:1)$4.00$0.45
RAG example (30K in / 2K out)$0.08$0.0084
Quality & speed
Intelligence Index38.4
Coding Index71.5
Agentic Index44.3
Output speed (tok/s)83
Time to first token105.20s
Specs
Context window1M1.05M
Input modalitiestext, image, filefile, image, text

FAQ

Which is cheaper, Claude Sonnet 5 or GPT-5.6 Luna Pro?

GPT-5.6 Luna Pro has the lower blended API price at $0.45 per 1M tokens (3:1 input:output mix), versus $4.00 for the other model. Prices are live from OpenRouter and refresh about hourly.

Which is better for RAG workloads?

For a typical RAG request (30K input / 2K output tokens), GPT-5.6 Luna Pro costs about $0.0084 per request versus $0.08. Also compare context windows: Claude Sonnet 5 offers 1M and GPT-5.6 Luna Pro offers 1.05M.

Which scores higher on Artificial Analysis benchmarks?

Claude Sonnet 5 leads on the Artificial Analysis Intelligence Index (38.4 vs —). Check coding and agentic indices on this page for workload-specific tradeoffs.