The AI arena is free today

Open Superagent

o3-pro vs Phi 4 Reasoning

Comparing o3-pro and Phi 4 Reasoning across benchmarks, pricing, and capabilities.

OpenAI · Microsoft · Updated for 2026

Which is better?

o3-pro and Phi 4 Reasoning trade strengths across price, capabilities, and technical limits. The better choice depends on the workload.

Based on current LLM Stats indexes, shared benchmarks, pricing, and model metadata for 2026.

Choose o3-pro

  • you want the most recent training data — it shipped Jun 2025

Choose Phi 4 Reasoning

  • you need open weights you can self-host or fine-tune

At a glance

The differences that matter most.

o3-pro
OpenAI
Phi 4 Reasoning
Microsoft
Benchmark wins
—
—
Input price
$20.00 / M
— / M
Output price
$80.00 / M
— / M
Context window
200,000
—

Individual benchmarks

0 reported for o3-pro · 11 for Phi 4 Reasoning

No common benchmarks found

o3-pro and Phi 4 Reasoningdon't have any common benchmark datasets to compare. They may have been evaluated on different testing suites.

Human preference

Blind head-to-head votes and playground preference scores

Context Window

Maximum input and output token capacity

Only o3-pro specifies input context (200,000 tokens). Only o3-pro specifies output context (100,000 tokens).

OpenAI
o3-pro
Input200,000 tokens
Output100,000 tokens
Microsoft
Phi 4 Reasoning
Input- tokens
Output- tokens
Wed Sep 23 2026 • llm-stats.com

Input capabilities

Documented input modalities across available providers

o3-pro supports multimodal inputs, whereas Phi 4 Reasoning does not.

o3-pro can handle both text and other forms of data like images, making it suitable for multimodal applications.

o3-pro

Text
Images
Audio
Video

Phi 4 Reasoning

Text
Images
Audio
Video

License

Usage and distribution terms

o3-pro is licensed under a proprietary license, while Phi 4 Reasoning uses MIT.

License differences may affect how you can use these models in commercial or open-source projects.

o3-pro

Proprietary

Closed source

Phi 4 Reasoning

MIT

Open weights

Release Timeline

When each model was launched

o3-pro was released on 2025-06-10, while Phi 4 Reasoning was released on 2025-04-30.

o3-pro is 1 month newer than Phi 4 Reasoning.

o3-pro

Jun 10, 2025

1.3 years ago

1mo newer
Phi 4 Reasoning

Apr 30, 2025

1.4 years ago

Knowledge Cutoff

When training data ends

o3-pro has a knowledge cutoff of 2024-05-31, while Phi 4 Reasoning has a cutoff of 2025-03-01.

Phi 4 Reasoning has more recent training data (up to 2025-03-01), making it potentially better informed about events through that date compared to o3-pro (2024-05-31).

o3-pro

May 2024

Phi 4 Reasoning

Mar 2025

10 mo newer

Outputs Comparison

Notice missing or incorrect data?Start an Issue discussion→

Judge for yourself.

Run your own prompts against o3-pro and Phi 4 Reasoning side-by-side, then vote on the output you prefer.

o3-pro
✓ Preferred
Phi 4 Reasoning
Open in Playground

FAQ

Common questions about o3-pro vs Phi 4 Reasoning.

Which is better, o3-pro or Phi 4 Reasoning?

o3-pro (OpenAI) and Phi 4 Reasoning (Microsoft) each have strengths in different areas. Compare their benchmark scores, pricing, context windows, and capabilities above to determine which fits your needs.

How does o3-pro compare to Phi 4 Reasoning in benchmarks?

Phi 4 Reasoning scores FlenQA: 97.7%, HumanEval+: 92.9%, IFEval: 83.4%, OmniMath: 76.6%, AIME 2024: 75.3%.

What are the context window sizes for o3-pro and Phi 4 Reasoning?

o3-pro supports 200K tokens and Phi 4 Reasoning supports an unknown number of tokens. A larger context window lets you process longer documents, conversations, or codebases in a single request.

What are the main differences between o3-pro and Phi 4 Reasoning?

Key differences include multimodal support (yes vs no), licensing (Proprietary vs MIT). See the full comparison above for benchmark-by-benchmark results.

Who makes o3-pro and Phi 4 Reasoning?

o3-pro is developed by OpenAI and Phi 4 Reasoning is developed by Microsoft.

Related comparisons