OpenAI: GPT-5.6 Terra Pro (batch) vs Google: Gemini 3.5 Flash: Live Promos, Pricing, Hidden Fees & Latency
Verified 2026 FinOps benchmark comparing OpenAI: GPT-5.6 Terra Pro (batch) (openai/gpt-5.6-terra-pro:batch) vs Google: Gemini 3.5 Flash (google/gemini-3.5-flash). Simulate cache read multipliers, context cliffs, MAU bills, and P90 latency.
OpenAI: GPT-5.6 Terra Pro (batch) (openai/gpt-5.6-terra-pro:batch) 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 3.5 Flash (google/gemini-3.5-flash) — 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-5.6 Terra Pro (batch) (API ID: openai/gpt-5.6-terra-pro:batch) vs Google: Gemini 3.5 Flash (API ID: google/gemini-3.5-flash), OpenAI: GPT-5.6 Terra Pro (batch) offers lower standard input pricing at $1/1M tokens ($6/1M output), while OpenAI: GPT-5.6 Terra Pro (batch) leads in cached prefix economics at $0.5/1M tokens (50% discount). OpenAI: GPT-5.6 Terra Pro (batch) achieves a 0ms faster P90 time-to-first-token latency (280ms vs 280ms).
Auto-discovered via live global telemetry registry.
Auto-discovered via live global telemetry registry.
| Specification / FinOps Dimension | OpenAI: GPT-5.6 Terra Pro (batch) | Google: Gemini 3.5 Flash | Verified Advantage |
|---|---|---|---|
| Official Vendor API ID | openai/gpt-5.6-terra-pro:batch | google/gemini-3.5-flash | Pinned Snapshot IDs |
| Standard Input / Output (per 1M) | $1 / $6 | $1.5 / $9 | OpenAI: GPT-5.6 Terra Pro (batch) |
| Cache Read Price (per 1M) | $0.5/1M (50% Off) | $0.75/1M (50% Off) | OpenAI: GPT-5.6 Terra Pro (batch) |
| Context Window / Max Output | 1025K In / 125K Out | 1024K In / 64K Out | OpenAI: GPT-5.6 Terra Pro (batch) |
| P90 First-Token / Edge Latency | 280ms | 280ms | OpenAI: GPT-5.6 Terra Pro (batch) (-0ms) |
GPT-5.6 Terra Pro is the same underlying model as [GPT-5.6 Terra](https://openrouter.ai/openai/gpt-5.6-terra), served with `reasoning.mode` set to `pro` for higher-quality response
Gemini 3.5 Flash is Google's high-efficiency multimodal model, bringing near-Pro level coding and reasoning at Flash-tier cost and speed. It is highly optimized for coding proficie
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-5.6 Terra Pro (batch) to Google: Gemini 3.5 Flash
Gemini 3.5 Flash is Google's high-efficiency multimodal model, bringing near-Pro level coding and reasoning at Flash-tier cost and speed. It is highly optimized for coding proficie Verified P90 latency of 280ms.