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Claude Sonnet 5 vs GPT-5.6 Luna

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

Prices updated Jul 22, 2026, 1:39 AM UTC · refreshed hourly

Claude Sonnet 5

Anthropic

GPT-5.6 Luna

OpenAI

Pricing
Input $/1M$2.00$1.00
Output $/1M$10.00$6.00
Blended $/1M (3:1)$4.00$2.25
RAG example (30K in / 2K out)$0.08$0.042
Quality & speed
Intelligence Index53.451.2
Coding Index71.571.4
Agentic Index46.745.6
Output speed (tok/s)88203
Time to first token93.55s102.47s
Specs
Context window1M1.05M
Input modalitiestext, image, filefile, image, text

FAQ

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

GPT-5.6 Luna has the lower blended API price at $2.25 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 costs about $0.042 per request versus $0.08. Also compare context windows: Claude Sonnet 5 offers 1M and GPT-5.6 Luna offers 1.05M.

Which scores higher on Artificial Analysis benchmarks?

Claude Sonnet 5 leads on the Artificial Analysis Intelligence Index (53.4 vs 51.2). Check coding and agentic indices on this page for workload-specific tradeoffs.