# Phi-4-reasoning — API, pricing & specs via nRouter

> Phi-4-reasoning is available through nRouter, the managed LLM gateway: one OpenAI-compatible API key, 0% token markup (exact provider list pricing), 0% platform fee, built-in guardrails, and per-request cost tracking.

## What it is

Phi-4-reasoning is Microsoft's 14-billion parameter reasoning model specialized in step-by-step logical deduction, STEM proofs, and rigorous code verification.

Source: https://learn.microsoft.com/en-us/azure/foundry/foundry-models/concepts/models-from-partners

## Facts

- Maker: Microsoft
- Released: 2025-02-26
- Served on: Azure Foundry

## nRouter list pricing (exact provider rates, 0% markup)

- Input: $0.125 per 1M tokens
- Output: $0.5 per 1M tokens

Settled at the exact provider list price above. nRouter adds no per-token markup and charges a 0% platform fee (see https://nrouter.ai/pricing).

## Use it

```python
from openai import OpenAI

client = OpenAI(
    base_url="https://api.nrouter.ai/v1",
    api_key="sk-nrouter-YOUR_KEY",  # create one at https://nrouter.ai/signup
)

response = client.chat.completions.create(
    model="azure_ai/Phi-4-reasoning",
    messages=[{"role": "user", "content": "Hello"}],
)
```

Model page: https://nrouter.ai/models/phi-4-reasoning
Full nRouter index for AI engines: https://nrouter.ai/llms.txt
Docs: https://nrouter.ai/docs