Microsoft: Phi 4 vs OpenAI: GPT Luna Latest: Live Promos, Pricing, Hidden Fees & Latency
Verified 2026 FinOps benchmark comparing Microsoft: Phi 4 (microsoft/phi-4) vs OpenAI: GPT Luna Latest (~openai/gpt-luna-latest). Simulate cache read multipliers, context cliffs, MAU bills, and P90 latency.
Microsoft: Phi 4 (microsoft/phi-4) 2026 Q4 Developer Promotion & Volume Credits
Official 2026 Q4 promotion for Microsoft: Phi 4: Activate ephemeral prefix caching to slash input costs by 50% (down to $0.035/1M) or route via asynchronous Batch API for 50% off standard token rates.
OpenAI: GPT Luna Latest (~openai/gpt-luna-latest) 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 Microsoft: Phi 4 (API ID: microsoft/phi-4) vs OpenAI: GPT Luna Latest (API ID: ~openai/gpt-luna-latest), Microsoft: Phi 4 offers lower standard input pricing at $0.07/1M tokens ($0.14/1M output), while Microsoft: Phi 4 leads in cached prefix economics at $0.035/1M tokens (50% discount). Microsoft: Phi 4 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 | Microsoft: Phi 4 | OpenAI: GPT Luna Latest | Verified Advantage |
|---|---|---|---|
| Official Vendor API ID | microsoft/phi-4 | ~openai/gpt-luna-latest | Pinned Snapshot IDs |
| Standard Input / Output (per 1M) | $0.07 / $0.14 | $0.1 / $0.5 | Microsoft: Phi 4 |
| Cache Read Price (per 1M) | $0.035/1M (50% Off) | $0.05/1M (50% Off) | Microsoft: Phi 4 |
| Context Window / Max Output | 16K In / 14K Out | 1025K In / 125K Out | OpenAI: GPT Luna Latest |
| P90 First-Token / Edge Latency | 280ms | 280ms | Microsoft: Phi 4 (-0ms) |
[Microsoft Research](/microsoft) Phi-4 is designed to perform well in complex reasoning tasks and can operate efficiently in situations with limited memory or where quick responses
This model always redirects to the latest model in the GPT Luna family.
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 Microsoft: Phi 4 to OpenAI: GPT Luna Latest
This model always redirects to the latest model in the GPT Luna family. Verified P90 latency of 280ms.