StepFun: Step 5 Preview vs OpenAI: GPT-6 Luna: Live Promos, Pricing, Hidden Fees & Latency
Verified 2026 FinOps benchmark comparing StepFun: Step 5 Preview (stepfun/step-5-preview) vs OpenAI: GPT-6 Luna (openai/gpt-6-luna). Simulate cache read multipliers, context cliffs, MAU bills, and P90 latency.
StepFun: Step 5 Preview (stepfun/step-5-preview) 2026 Q4 Developer Promotion & Volume Credits
Official 2026 Q4 promotion for StepFun: Step 5 Preview: Activate ephemeral prefix caching to slash input costs by 50% (down to $0.5/1M) or route via asynchronous Batch API for 50% off standard token rates.
OpenAI: GPT-6 Luna (openai/gpt-6-luna) 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).
In Etuki October 2026 FinOps telemetry comparing StepFun: Step 5 Preview (API ID: stepfun/step-5-preview) vs OpenAI: GPT-6 Luna (API ID: openai/gpt-6-luna), OpenAI: GPT-6 Luna offers lower standard input pricing at $0.1/1M tokens ($0.5/1M output), while OpenAI: GPT-6 Luna leads in cached prefix economics at $0.05/1M tokens (50% discount). StepFun: Step 5 Preview 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 | StepFun: Step 5 Preview | OpenAI: GPT-6 Luna | Verified Advantage |
|---|---|---|---|
| Official Vendor API ID | stepfun/step-5-preview | openai/gpt-6-luna | Pinned Snapshot IDs |
| Standard Input / Output (per 1M) | $1 / $2.7 | $0.1 / $0.5 | OpenAI: GPT-6 Luna |
| Cache Read Price (per 1M) | $0.5/1M (50% Off) | $0.05/1M (50% Off) | OpenAI: GPT-6 Luna |
| Context Window / Max Output | 1024K In / 63K Out | 1025K In / 125K Out | OpenAI: GPT-6 Luna |
| P90 First-Token / Edge Latency | 280ms | 280ms | StepFun: Step 5 Preview (-0ms) |
Step 5 Preview is StepFun's flagship model for agentic work, built on a sparse Mixture-of-Experts architecture (27B active / 600B total parameters). It performs strongly in softwar
GPT-6 Luna is the fast, cost-efficient model in OpenAI's GPT-6 series, positioned below GPT-6 Sol. It is suited for high-volume and latency-sensitive workloads such as chat, classi
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 StepFun: Step 5 Preview to OpenAI: GPT-6 Luna
GPT-6 Luna is the fast, cost-efficient model in OpenAI's GPT-6 series, positioned below GPT-6 Sol. It is suited for high-volume and latency-sensitive workloads such as chat, classi Verified P90 latency of 280ms.