ModelRefs / Phi-4 vs o3
Phi-4 vs o3
Phi-4 vs o3: side-by-side benchmarks, pricing, context windows, coding ability and deployment. Pick the right model for your stack.
Overview
o3: o3 is OpenAI's April 2025 reasoning model, applying deliberate chain-of-thought computation at inference time to mathematics, science and competitive programming tasks, and the release that brought OpenAI's scalable test-time compute approach to its production API. OpenAI has since deprecated it, scheduling the o3-2025-04-16 snapshot to shut down on 11 December 2026 with gpt-5.6-sol as the replacement.
Phi-4: Microsoft's 14B dense decoder-only open-weight text model, trained on 9.8T tokens with a synthetic-data-centered curriculum and available through the microsoft/phi-4 artifact and Microsoft Foundry.
Context window: o3 accepts up to 200,000 tokens, Phi-4 up to 16,384. Confirm the limit for your specific deployment channel before relying on it.
o3 vs Phi-4 at a glance
| Attribute | o3 | Phi-4 |
|---|---|---|
| Provider | OpenAI | Microsoft |
| Released | 2025-04-16 | 2024-12-12 |
| Context window | 200,000 tokens | 16,384 tokens |
| Input price | $10/M tokens | Free / self-hosted |
| Output price | $40/M tokens | Free / self-hosted |
| Licence | Proprietary | MIT |
| Self-hostable | No, hosted only | Yes, open weights |
| Modalities | text, vision | text |
Benchmarks reported for both
| Benchmark | o3 | Phi-4 | Reported |
|---|---|---|---|
| GPQA Diamond (accuracy) | 82.8 | 56.1 | 2024-12-12 |
Each row compares the same benchmark, the same reported metric, and the same task set. Scores are as published by their cited sources on the dates shown. Different runs still use different harnesses and prompts, so treat these as directional evidence rather than a head-to-head result.
Where they differ most
- Cost Efficiency: o3 13%, Phi-4 100%. Phi-4 leads on this dimension.
- Reasoning: o3 86%, Phi-4 61%. o3 leads on this dimension.
Capability scores are ModelRefs' own derived signals, not vendor claims or benchmark results. Validate against your own workload before relying on them.
Continue your research
Use these connected ModelRefs sections to compare alternatives, inspect implementation paths, and review the evidence and governance boundaries relevant to Phi-4 vs o3.
Frequently asked questions
Which is better, Phi-4 or o3?
Phi-4 and o3 target different workloads — see the benchmark and pricing tables for a side-by-side answer.
Is Phi-4 cheaper than o3?
Compare $0.00000 vs $0.0100 on this page.