OpenAI: GPT-5.2-Codex vs StepFun: Step 3.5 Flash: Live Promos, Pricing, Hidden Fees & Latency
Verified 2026 FinOps benchmark comparing OpenAI: GPT-5.2-Codex (openai/gpt-5.2-codex) vs StepFun: Step 3.5 Flash (stepfun/step-3.5-flash). Simulate cache read multipliers, context cliffs, MAU bills, and P90 latency.
OpenAI: GPT-5.2-Codex (openai/gpt-5.2-codex) 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).
StepFun: Step 3.5 Flash (stepfun/step-3.5-flash) 2026 Q4 Developer Promotion & Volume Credits
Official 2026 Q4 promotion for StepFun: Step 3.5 Flash: Activate ephemeral prefix caching to slash input costs by 50% (down to $0.05/1M) or route via asynchronous Batch API for 50% off standard token rates.
In Etuki October 2026 FinOps telemetry comparing OpenAI: GPT-5.2-Codex (API ID: openai/gpt-5.2-codex) vs StepFun: Step 3.5 Flash (API ID: stepfun/step-3.5-flash), StepFun: Step 3.5 Flash offers lower standard input pricing at $0.1/1M tokens ($0.3/1M output), while StepFun: Step 3.5 Flash leads in cached prefix economics at $0.05/1M tokens (50% discount). OpenAI: GPT-5.2-Codex 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-5.2-Codex | StepFun: Step 3.5 Flash | Verified Advantage |
|---|---|---|---|
| Official Vendor API ID | openai/gpt-5.2-codex | stepfun/step-3.5-flash | Pinned Snapshot IDs |
| Standard Input / Output (per 1M) | $1.75 / $14 | $0.1 / $0.3 | StepFun: Step 3.5 Flash |
| Cache Read Price (per 1M) | $0.875/1M (50% Off) | $0.05/1M (50% Off) | StepFun: Step 3.5 Flash |
| Context Window / Max Output | 391K In / 125K Out | 256K In / 64K Out | OpenAI: GPT-5.2-Codex |
| P90 First-Token / Edge Latency | 280ms | 280ms | OpenAI: GPT-5.2-Codex (-0ms) |
GPT-5.2-Codex is an upgraded version of GPT-5.1-Codex optimized for software engineering and coding workflows. It is designed for both interactive development sessions and long, in
Step 3.5 Flash is StepFun's most capable open-source foundation model. Built on a sparse Mixture of Experts (MoE) architecture, it selectively activates only 11B of its 196B parame
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-5.2-Codex to StepFun: Step 3.5 Flash
Step 3.5 Flash is StepFun's most capable open-source foundation model. Built on a sparse Mixture of Experts (MoE) architecture, it selectively activates only 11B of its 196B parame Verified P90 latency of 280ms.