# Phi-4 Reasoning Plus ![Organization](https://img.shields.io/badge/Org-Microsoft-0078d4) ![Parameters](https://img.shields.io/badge/Params-14B-1f6feb) ![Context](https://img.shields.io/badge/Context-32K%20tokens-1f6feb) ![License](https://img.shields.io/badge/License-Apache%202.0-2da44e) ![Weights](https://img.shields.io/badge/Weights-Open-2da44e) ![Released](https://img.shields.io/badge/Released-Apr%202025-555) > **Quick answer:** Phi-4 Reasoning Plus is Microsoft's April 2025 open-weight reasoning variant of Phi-4, scoring 79% on Arena Hard, 53.1% on LiveCodeBench, and 76% on MMLU-Pro. It adds chain-of-thought reasoning to the base Phi-4 architecture with Apache 2.0 license — making it the strongest open reasoning model at the 14B scale. ## At a Glance **Where Phi-4 Reasoning Plus leads** - 76% MMLU-Pro — highest academic knowledge at 14B scale with reasoning - 79% Arena Hard — strong instruction following with reasoning - 53.1% LiveCodeBench — best open 14B coding performance - Apache 2.0 — fully permissive commercial use - 14B parameters — single-GPU deployable - Reasoning capability at small model scale **Where it lags** - 32K context window — significantly below larger models - Text-only: no vision support - Reasoning adds latency vs base Phi-4 - Knowledge cutoff September 2024 **Best for:** Open-weight reasoning at 14B scale; Apache 2.0 reasoning model for commercial deployments; STEM tasks requiring reasoning under GPU constraints. ## What Phi-4 Reasoning Plus Is Phi-4 Reasoning Plus is Microsoft's extension of Phi-4, adding explicit chain-of-thought reasoning training to the base 14B model. Released April 30, 2025, it was one of the first Apache 2.0 reasoning models at a deployable scale. The "Plus" variant represents the most capable version of Phi-4 Reasoning — trained with additional reasoning data and reinforcement learning to strengthen its thinking capability. With 76% MMLU-Pro, it surpasses the base Phi-4 (70.4%) on academic knowledge when reasoning is enabled. Phi-4 Reasoning Plus fills a distinctive niche: Apache 2.0 reasoning model under 20B parameters. For teams requiring a reasoning model that can be fine-tuned, self-hosted, and commercially deployed without proprietary restrictions, it is the primary open-weight option at this scale. ## Specifications | Field | Value | |---|---| | Organization | Microsoft | | Parameters | 14B (dense) | | Context window | 32,000 tokens | | License | Apache 2.0 | | HuggingFace | [microsoft/Phi-4-reasoning-plus](https://huggingface.co/microsoft/Phi-4-reasoning-plus) | | Release date | April 30, 2025 | | Knowledge cutoff | September 2024 | | Modality | Text only | ## Pricing Phi-4 Reasoning Plus is available as open weights under Apache 2.0 — free for self-hosting and commercial use. Available via Azure AI Foundry and third-party providers. ## Public Benchmark Scores | Benchmark | Score | Source | Date | |---|---|---|---| | [Arena Hard v2](/benchmarks/arena-hard-v2) | 79% | Benchgen evaluation | 2025-07 | | [LiveCodeBench](/benchmarks/livecodebench) | 53.1% | Benchgen evaluation | 2025-07 | | [MMLU-Pro](/benchmarks/mmlu-pro) | 76% | Benchgen evaluation | 2025-07 | ## Phi-4 Reasoning Plus vs Alternatives | Model | MMLU-Pro | LiveCodeBench | License | Reasoning | |---|---|---|---|---| | **Phi-4 Reasoning Plus** | 76% | 53.1% | Apache 2.0 | Yes | | [Phi-4](/models/microsoft/phi-4) | 70.4% | — | Apache 2.0 | No | | [QwQ 32B](/models/qwen/qwq-32b) | — | — | Apache 2.0 | Yes | | [Gemma 3 27B](/models/google/gemma-3-27b) | 67.5% | — | Gemma ToU | No | Phi-4 Reasoning Plus vs Phi-4: +5.6pp MMLU-Pro (76% vs 70.4%), stronger coding (53.1% LiveCodeBench). At 2× the latency due to reasoning steps. Choose Phi-4 for speed; Phi-4 Reasoning Plus for accuracy on complex tasks. ## Related Models & Benchmarks - Compare: [Phi-4](/models/microsoft/phi-4) · [QwQ 32B](/models/qwen/qwq-32b) · [Gemma 3 27B](/models/google/gemma-3-27b) - Benchmarks: [Arena Hard v2](/benchmarks/arena-hard-v2) · [LiveCodeBench](/benchmarks/livecodebench) · [MMLU-Pro](/benchmarks/mmlu-pro) ## Frequently Asked Questions

What is Phi-4 Reasoning Plus?

Phi-4 Reasoning Plus is Microsoft's April 2025 reasoning variant of Phi-4, scoring 79% Arena Hard, 53.1% LiveCodeBench, and 76% MMLU-Pro. It adds chain-of-thought reasoning to the 14B Phi-4 architecture under Apache 2.0.

Is Phi-4 Reasoning Plus open source?

Yes. Phi-4 Reasoning Plus is released under Apache 2.0 — free for commercial use without restrictions.

What is the difference between Phi-4 and Phi-4 Reasoning Plus?

Phi-4 is the base model with direct response generation. Phi-4 Reasoning Plus adds chain-of-thought reasoning training, improving accuracy on complex tasks (+5.6pp MMLU-Pro) at the cost of higher latency.

--- *Specs from Microsoft's official Phi-4 Reasoning release (April 2025) and Benchgen evaluations. Last updated 2026-07-24.*

Phi 4 Reasoning Plus — Files