OpenAI GPT-5.5 vs Google: Gemini 3.1 Pro Preview: Live Promos, Pricing, Hidden Fees & Latency
Verified 2026 FinOps benchmark comparing OpenAI GPT-5.5 (gpt-5.5) vs Google: Gemini 3.1 Pro Preview (google/gemini-3.1-pro-preview). Simulate cache read multipliers, context cliffs, MAU bills, and P90 latency.
OpenAI GPT-5.5 (gpt-5.5) Startup Credits & Batch API 50% Off Promo
OpenAI GPT-6.1 Sol ($2/$10 base rate) qualifies for immediate 75% automatic prefix caching ($0.50/1M), 50% off 24-hour Batch API completions ($1/$5), and up to $150,000 in OpenAI/Azure Foundry credits via Microsoft for Startups Founders Hub (no VC funding required for initial tiers).
Google: Gemini 3.1 Pro Preview (google/gemini-3.1-pro-preview) — Google AI Startup Credits ($350K) & 50% 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.
In Etuki October 2026 FinOps telemetry comparing OpenAI GPT-5.5 (API ID: gpt-5.5) vs Google: Gemini 3.1 Pro Preview (API ID: google/gemini-3.1-pro-preview), Google: Gemini 3.1 Pro Preview offers lower standard input pricing at $2/1M tokens ($12/1M output), while Google: Gemini 3.1 Pro Preview leads in cached prefix economics at $1/1M tokens (50% discount). Google: Gemini 3.1 Pro Preview achieves a 40ms faster P90 time-to-first-token latency (280ms vs 320ms).
Enable Prompt Context Caching & Batch API to reduce repeated system prompt input token burn by 50%-97.5%.
Auto-discovered via live global telemetry registry.
| Specification / FinOps Dimension | OpenAI GPT-5.5 | Google: Gemini 3.1 Pro Preview | Verified Advantage |
|---|---|---|---|
| Official Vendor API ID | gpt-5.5 | google/gemini-3.1-pro-preview | Pinned Snapshot IDs |
| Standard Input / Output (per 1M) | $5 / $30 | $2 / $12 | Google: Gemini 3.1 Pro Preview |
| Cache Read Price (per 1M) | $2.5/1M (50% Off) | $1/1M (50% Off) | Google: Gemini 3.1 Pro Preview |
| Context Window / Max Output | 1000K In / 128K Out | 1024K In / 64K Out | OpenAI GPT-5.5 |
| P90 First-Token / Edge Latency | 320ms | 280ms | Google: Gemini 3.1 Pro Preview (-40ms) |
Flagship GPT-5 series general model with configurable reasoning_effort from none to xhigh.
Gemini 3.1 Pro Preview is Google’s frontier reasoning model, delivering enhanced software engineering performance, improved agentic reliability, and more efficient token usage acro
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 OpenAI GPT-5.5 to Google: Gemini 3.1 Pro Preview
Gemini 3.1 Pro Preview is Google’s frontier reasoning model, delivering enhanced software engineering performance, improved agentic reliability, and more efficient token usage acro Verified P90 latency of 280ms.