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Phi 4 mini reasoning

Instantly via the EU router or as a dedicated GPU deployment. Data stays in Europe.

Phi-4-mini-reasoning is a lightweight open model built upon synthetic data with a focus on high-quality, reasoning dense data further finetuned for more advanced math reasoning capabilities. The model belongs to the Phi-4 model family and supports 128K token context length.

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microsoft/Phi-4-mini-reasoning vLLM ready
text->text · microsoft · EU-hosted
3.8B
Parameters
131K
Context window
9GB
Minimum VRAM
POST /api/v1/chat/completions200 OK

Specifications

Parameters 3.8B
Context window 131,072 tokens
Minimum VRAM 9 GB
Architecture Phi3ForCausalLM (vLLM)
License mit
Modality text->text
Released April 2025
Publisher microsoft ↗

Pricing

€0.05
Input (per 1M tokens)
€0.10
Output (per 1M tokens)

Shared EU router, pay-per-token, scale-to-zero. Dedicated GPU deployments are billed hourly — see pricing.

✓ Verified working on 29-06-2026 — responded in 665 ms on our EU infrastructure.

Call it now

Drop-in replacement for OpenAI: change only the base URL and API key. The Anthropic format (/v1/messages) is supported too.

curl https://hostyourai.com/api/v1/chat/completions \
  -H "Authorization: Bearer hyai-..." \
  -H "Content-Type: application/json" \
  -d '{
    "model": "microsoft/Phi-4-mini-reasoning",
    "messages": [{"role": "user", "content": "Hello!"}]
  }'

Frequently asked questions

Can I run Phi 4 mini reasoning in the EU?

Yes. HostYourAI runs Phi 4 mini reasoning on GPUs in European datacenters via vLLM. Prompts and outputs never leave the EU and there is no US cloud provider in the chain.

Is hosting Phi 4 mini reasoning GDPR-compliant?

Yes. All processing happens inside the EU, a Data Processing Agreement (DPA) is available and the subprocessor list is public. Open-source weights also mean: no training on your data.

How much does Phi 4 mini reasoning cost?

Via the shared EU router you pay €0.05 per million input tokens and €0.10 per million output tokens, with no fixed costs. For high volume or isolation you can also run Phi 4 mini reasoning as a dedicated hourly GPU instance.

Is the API OpenAI-compatible?

Yes. You use the standard OpenAI SDKs with a custom base URL (https://hostyourai.com/api/v1). The Anthropic Messages API is supported as a drop-in as well.

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