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Claude Sonnet 5 vs Gemini 3.8 Flash (batch)

Side-by-side API pricing and Artificial Analysis performance for Claude Sonnet 5 (Anthropic) and Gemini 3.8 Flash (batch) (Google). Green cells mark the better value in each row.

Prices updated Sep 19, 2026, 9:32 AM UTC · refreshed hourly

Claude Sonnet 5

Anthropic

Gemini 3.8 Flash (batch)

Google

Pricing
Input $/1M$2.00$0.375
Output $/1M$10.00$1.88
Blended $/1M (3:1)$4.00$0.75
RAG example (30K in / 2K out)$0.08$0.015
Quality & speed
Intelligence Index38.441.2
Coding Index71.576.3
Agentic Index44.341.1
Output speed (tok/s)86314
Time to first token116.56s10.73s
Specs
Context window1M1.05M
Input modalitiestext, image, filetext, image, video, file, audio

FAQ

Which is cheaper, Claude Sonnet 5 or Gemini 3.8 Flash (batch)?

Gemini 3.8 Flash (batch) has the lower blended API price at $0.75 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), Gemini 3.8 Flash (batch) costs about $0.015 per request versus $0.08. Also compare context windows: Claude Sonnet 5 offers 1M and Gemini 3.8 Flash (batch) offers 1.05M.

Which scores higher on Artificial Analysis benchmarks?

Gemini 3.8 Flash (batch) leads on the Artificial Analysis Intelligence Index (41.2 vs 38.4). Check coding and agentic indices on this page for workload-specific tradeoffs.