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Claude Sonnet 5 vs DeepSeek V4 Flash 0423

Side-by-side API pricing and Artificial Analysis performance for Claude Sonnet 5 (Anthropic) and DeepSeek V4 Flash 0423 (DeepSeek). Green cells mark the better value in each row.

Prices updated Sep 19, 2026, 5:17 PM UTC · refreshed hourly

Claude Sonnet 5

Anthropic

DeepSeek V4 Flash 0423

DeepSeek

Pricing
Input $/1M$2.00$0.041
Output $/1M$10.00$0.083
Blended $/1M (3:1)$4.00$0.052
RAG example (30K in / 2K out)$0.08$0.001409
Quality & speed
Intelligence Index38.434.5
Coding Index71.569.1
Agentic Index44.327.9
Output speed (tok/s)79234
Time to first token116.86s0.90s
Specs
Context window1M1.05M
Input modalitiestext, image, filetext

FAQ

Which is cheaper, Claude Sonnet 5 or DeepSeek V4 Flash 0423?

DeepSeek V4 Flash 0423 has the lower blended API price at $0.052 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), DeepSeek V4 Flash 0423 costs about $0.001409 per request versus $0.08. Also compare context windows: Claude Sonnet 5 offers 1M and DeepSeek V4 Flash 0423 offers 1.05M.

Which scores higher on Artificial Analysis benchmarks?

Claude Sonnet 5 leads on the Artificial Analysis Intelligence Index (38.4 vs 34.5). Check coding and agentic indices on this page for workload-specific tradeoffs.