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Claude Sonnet 5 vs GLM 5.3 Flash

Side-by-side API pricing and Artificial Analysis performance for Claude Sonnet 5 (Anthropic) and GLM 5.3 Flash (Z.ai). Green cells mark the better value in each row.

Prices updated Sep 19, 2026, 4:56 AM UTC · refreshed hourly

Claude Sonnet 5

Anthropic

GLM 5.3 Flash

Z.ai

Pricing
Input $/1M$2.00$0.09
Output $/1M$10.00$0.30
Blended $/1M (3:1)$4.00$0.143
RAG example (30K in / 2K out)$0.08$0.0033
Quality & speed
Intelligence Index38.441.9
Coding Index71.571.5
Agentic Index44.351.2
Output speed (tok/s)80
Time to first token119.93s
Specs
Context window1M1.31M
Input modalitiestext, image, filetext, image, video

FAQ

Which is cheaper, Claude Sonnet 5 or GLM 5.3 Flash?

GLM 5.3 Flash has the lower blended API price at $0.143 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), GLM 5.3 Flash costs about $0.0033 per request versus $0.08. Also compare context windows: Claude Sonnet 5 offers 1M and GLM 5.3 Flash offers 1.31M.

Which scores higher on Artificial Analysis benchmarks?

GLM 5.3 Flash leads on the Artificial Analysis Intelligence Index (41.9 vs 38.4). Check coding and agentic indices on this page for workload-specific tradeoffs.