Gemini 3.1 Pro Preview vs GLM 5.3 Prime
API pricing, context, and independently measured performance, side by side. Gemini 3.1 Pro Preview starts 29% cheaper on input than GLM 5.3 Prime at list prices.
Gemini 3.1 Pro Preview
Google · released Feb 19, 2026
Best input$2.00 / MTok
Best output$12.00 / MTok
Context1.05M
Providers8
Fastest measured2.6s° TTFT · 305 tok/s
VisionToolsReasoningStructured outputPrompt caching
GLM 5.3 Prime
Z.ai · released Sep 23, 2026
Best input$2.80 / MTok
Best output$8.80 / MTok
Context1M
Providers1
Fastest measured—
ToolsReasoningStructured outputPrompt caching
Cheapest providers, measuredUSD / MTOK
| MODEL | PROVIDER | INPUT | OUTPUT | TTFT | TPS | SMOKE |
|---|---|---|---|---|---|---|
| Gemini 3.1 Pro Preview |  Google | $2.00 | $12.00 | 2.6s° | 305° tok/s | — |
| Gemini 3.1 Pro Preview |  Google AI Studio | $2.00 | $12.00 | 7.4s° | 318° tok/s | — |
| GLM 5.3 Prime |  Alibaba | $2.80 | $8.80 | — | — | — |
TTFT/TPS: ModelIndex-measured medians (P50, trailing 21d) · chat10k profile (~10K in / 200 out) · ° = measured via OpenRouter routing (adds a hop) · SMOKE: of 5 programmatic capability probes passed · methodology v1.1 — full details on each model page