Google Gemini 3.1 Pro vs Google Gemini 4 Argon: Live Promos, Pricing, Hidden Fees & Latency
Google Gemini 3.1 Pro (gemini-3.1-pro) — Google AI Startup Credits ($350K) & 90% Cache Promo
Google DeepMind is currently subsidizing Gemini 4 Argon at 50% off standard rates ($2.00/1M input & $10.00/1M output instead of $4/$20) until November 30, 2026, alongside 95% off Context Caching ($0.10/1M) and up to $350,000 in Google for Startups Cloud/Vertex AI credits.
Gemini 4 Argon 50% Introductory API Discount ($2/$10) & Google AI Startup Grants
Google DeepMind is currently subsidizing Gemini 4 Argon at 50% off standard rates ($2.00/1M input & $10.00/1M output instead of $4/$20) until November 30, 2026, alongside 95% off Context Caching ($0.10/1M) and up to $350,000 in Google for Startups Cloud/Vertex AI credits.
In Etuki October 2026 FinOps telemetry comparing Google Gemini 3.1 Pro (API ID: gemini-3.1-pro) vs Google Gemini 4 Argon (API ID: gemini-4-argon), Google Gemini 3.1 Pro offers lower standard input pricing at $2/1M tokens ($12/1M output), while Google Gemini 4 Argon leads in cached prefix economics at $0.1/1M tokens (95% discount). Google Gemini 4 Argon achieves a 160ms faster P90 time-to-first-token latency (130ms vs 290ms).
Enable Prompt Context Caching & Batch API to reduce repeated system prompt input token burn by 50%-97.5%.
⚠️ Time-Limited Intro Pricing Alert: The $2.00/$10.00 (Cache $0.10) rate expires on 2026-11-30! Starting 2026-12-01, standard pricing doubles to $4.00/$20.00 (Cache $0.20).
| Specification / FinOps Dimension | Google Gemini 3.1 Pro | Google Gemini 4 Argon | Verified Advantage |
|---|---|---|---|
| Official Vendor API ID | gemini-3.1-pro | gemini-4-argon | Pinned Snapshot IDs |
| Standard Input / Output (per 1M) | $2 / $12 | $2 / $10 | Google Gemini 3.1 Pro |
| Cache Read Price (per 1M) | $0.2/1M (90% Off) | $0.1/1M (95% Off) | Google Gemini 4 Argon |
| Context Window / Max Output | 2000K In / 128K Out | 1000K In / 1000K Out | Google Gemini 4 Argon |
| P90 First-Token / Edge Latency | 290ms | 130ms | Google Gemini 4 Argon (-160ms) |
Google 2M context multimodal model (<=200K: $2.00/$12.00, $0.20 cache; >200K cliff: $4.00/$18.00, 180K soft-block).
Google Oct 1, 2026 multimodal flagship currently at $2/$10 (Cache $0.10/1M) Time-Limited Intro Price through Nov 30, 2026; increases to $4/$20 (Cache $0.20) on Dec 1, 2026.
Real-Time Stack Cost & Hidden-Fee Simulator (MAU / Token / Egress / GMV)
Calibrated with Reddit r/FinOps & r/devops telemetry: Includes Context Caching, Bandwidth Egress, and MoR Tax
💎Switch from Google Gemini 3.1 Pro to Google Gemini 4 Argon
Google Oct 1, 2026 multimodal flagship currently at $2/$10 (Cache $0.10/1M) Time-Limited Intro Price through Nov 30, 2026; increases to $4/$20 (Cache $0.20) on Dec 1, 2026. Verified P90 latency of 130ms.