AI Models · Open-Source vs Paid

Phi 4 Open vs o3 Paid

Phi 4 vs o3 compared — price per token, context window, multimodality, openness and which to choose. Can the open-source model replace the paid one? Full 2026 breakdown.

Prices & specs refreshed from live data · olud.ai

Open-model prices = cheapest provider via OpenRouter; official maker rates may be higher.

Phi 4OpenMicrosoft
$0.07 /M input
$0.14 /M outputNo per-token fees if you self-host
TypeOpen-weight
Context window16K tokens
MultimodalNo
Self-hostYes
o3PaidOpenAI
$2 /M input
$8 /M outputManaged API (no infra to run)
TypeProprietary
Context window200K tokens
MultimodalYes
Self-hostNo
Choose Phi 4 if you want to self-host, keep your data private and skip per-token fees — it's open-weight and runs on your own hardware. Choose o3 if you want frontier capability through a managed API with zero infrastructure to run.

Phi 4 vs o3 specs

SpecPhi 4o3Winner
MakerMicrosoftOpenAI
TypeOpen-weightProprietaryPhi 4
Context window16K tokens200K tokenso3
Input price$0.07/M · free self-host$2/MPhi 4
Output price$0.14/M · free self-host$8/MPhi 4
Vision / multimodalNoYeso3
Tool / function callingNoYeso3
Self-hostableYesNo (API only)Phi 4
LicenseMITProprietaryPhi 4

Price gap & when to choose each

57×cheaper per output token

Phi 4 is ~57× cheaper than o3 on output tokens ($0.14 vs $8 per M tokens).

Choose Phi 4 if…
  • You want to self-host or run on your cloud
  • You prioritize data privacy & control
  • You want the lowest operating costs
  • You are building open or reproducible AI
Choose o3 if…
  • You want frontier performance through a managed API
  • You need the longer 200K context window
  • You value reliability & ecosystem
  • You don't want to manage infrastructure

Feature comparison

CapabilityPhi 4o3
Open weights (downloadable)
Self-hostable
Runs fully offline
Vision / multimodal
Tool / function calling
1M+ context window

Benchmarks: Phi 4 vs o3

Independent benchmark scores measured by Artificial Analysis. Higher is better (except latency).

Phi 4 delivers 4.6× more intelligence per dollar.
Phi 4
o3
Intelligence index
5.9
20.2
Math index
18
88.3
GPQA
57.5%
82.7%
MMLU-Pro
71.4%
85.3%
Humanity's Last Exam
3.8%
20.1%
Long Context Reasoning
0%
74.7%
LiveCodeBench
23.1%
80.8%
MATH-500
81%
99.2%
AIME
14.3%
90.3%
AIME 2025
18%
88.3%
IFBench
23.5%
71.4%
τ²-Bench
0%
80.7%
Terminal-Bench Hard
3.8%
37.1%
Speed
43.7 tok/s
114.5 tok/s
Latency
0.95s
6.58s
Intelligence per $
26.9
5.8

Benchmark data by Artificial Analysis.

How Phi 4 and o3 score

🏆 Best value & openness: Phi 4 (3.8 vs 3.0 / 5)
CriterionPhi 4o3
Cost-efficiency5.03.5
Context window2.04.0
Openness5.01.5
Self-hosting5.01.0
Multimodality2.05.0

Scores come from live data — output price (cost), context length, open vs closed weights (openness & self-hosting) and vision/tool support (multimodality). Raw task quality isn't scored here; it depends on your benchmark — see the verdict.

What each model is

Phi 4 Open

Microsoft · Open-weight

[Microsoft Research](/microsoft) Phi-4 is designed to perform well in complex reasoning tasks and can operate efficiently in situations with limited memory or where quick responses are needed. At 14 billion...

o3 Paid

OpenAI · Proprietary

o3 is a well-rounded and powerful model across domains. It sets a new standard for math, science, coding, and visual reasoning tasks. It also excels at technical writing and instruction-following....

Other models in these families

These variants are tracked but not compared here — one page per family keeps the comparison readable.

Other variants tracked
o3 Proo3 (batch)o3 Minio3 Mini (batch)o3 Mini High

Frequently asked questions

Is Phi 4 as good as o3?

Phi 4 is open-weight and competitive on many tasks, but o3 may still lead on the hardest reasoning and agentic work. The gap keeps narrowing — benchmark both on your actual use case before deciding.

Can I run Phi 4 locally?

Yes. Phi 4 has open weights, so you can self-host it on your own GPUs or run it via a low-cost API. o3 is API-only and cannot be self-hosted.

How much cheaper is Phi 4?

Phi 4 costs $0.14/M output vs $8/M for o3 — roughly 57x cheaper via API, and free if you self-host.

Phi 4 vs o3 — which should I pick in 2026?

Choose Phi 4 if you want to self-host, keep your data private and skip per-token fees — it's open-weight and runs on your own hardware. Choose o3 if you want frontier capability through a managed API with zero infrastructure to run.

People also compare

Explore more open-source AI

Browse the full open-source model leaderboard, thousands of tools and live benchmarks — all in one place.

Open the leaderboard →