Head-to-head · frontier vs frontier

Gemini 2.5 Pro Reasoning vs o4 Vision: which model should you choose?

We compared Gemini 2.5 Pro Reasoning and o4 Vision on price, context window and 12 benchmarks. o4 Vision has the stronger average benchmark score; Gemini 2.5 Pro Reasoning is cheaper on a blended 3:1 basis.

Google DeepMind

Gemini 2.5 Pro Reasoning

Gemini 2.5 Pro Reasoning is a frontier model from Google DeepMind. It offers a 128,000-token context window, costs $16.81 per million input tokens and $67.95 per million output tokens, and averages 83.8 across the index's benchmark suite.

Input
$16.81 / 1M
Output
$67.95 / 1M
Context
128,000
Avg score
83.8
Open weights
No
Full Gemini 2.5 Pro Reasoning page
OpenAI

o4 Vision

o4 Vision is a frontier model from OpenAI. It offers a 200,000-token context window, costs $17.01 per million input tokens and $90.05 per million output tokens, and averages 84.5 across the index's benchmark suite.

Input
$17.01 / 1M
Output
$90.05 / 1M
Context
200,000
Avg score
84.5
Open weights
No
Full o4 Vision page

Specification comparison

SpecGemini 2.5 Pro Reasoningo4 VisionEdge
Input price / 1M$16.81$17.01A
Output price / 1M$67.95$90.05A
Context window128,000200,000B
Max output4,0964,096Tie
Average score83.884.5B
Arena Elo1472.11473.2B
Open weightsNoNoTie

Benchmark comparison

Gemini 2.5 Pro Reasoning wins 5, o4 Vision wins 7, and 0 benchmarks are tied. The table shows the modelled score for each model and the gap.

BenchmarkGemini 2.5 Pro Reasoningo4 VisionGapWinner
MMLU-Pro86.884.22.6Gemini 2.5 Pro Reasoning
GPQA Diamond80.080.90.9o4 Vision
SWE-bench Verified71.275.64.4o4 Vision
HumanEval86.788.92.2o4 Vision
MATH-50087.991.73.8o4 Vision
AIME 202584.280.43.8Gemini 2.5 Pro Reasoning
LiveCodeBench74.881.36.5o4 Vision
IFEval90.889.11.7Gemini 2.5 Pro Reasoning
TruthfulQA84.085.31.3o4 Vision
HellaSwag92.191.20.9Gemini 2.5 Pro Reasoning
MMMU82.880.72.1Gemini 2.5 Pro Reasoning
Arena Elo1472.11473.21.1o4 Vision

Price analysis

On a blended 3:1 input-to-output basis, Gemini 2.5 Pro Reasoning costs about $29.59 per million tokens and o4 Vision costs about $35.27. Gemini 2.5 Pro Reasoning is roughly 16% cheaper than o4 Vision. At high volume, that gap compounds quickly, so price should carry real weight unless the quality difference is decisive.

o4 Vision has the larger context window at 200,000 tokens, compared with 128,000 for Gemini 2.5 Pro Reasoning. That matters for long documents, large codebases and multi-step agent traces.

Verdict

Across 12 shared benchmarks, Gemini 2.5 Pro Reasoning wins 5, o4 Vision wins 7, and 0 are tied. On the index average, o4 Vision leads Gemini 2.5 Pro Reasoning by 0.7 points (84.5 versus 83.8).

The price picture favours Gemini 2.5 Pro Reasoning. The context picture favours o4 Vision. Those two dimensions often matter more than a few benchmark points once a model is good enough for the task.

If you need a single default, start with o4 Vision for quality-sensitive work and Gemini 2.5 Pro Reasoning for high-volume, well-scoped tasks. Run both on a sample of your own traffic before locking in a choice.

Choose Gemini 2.5 Pro Reasoning if

  • Unit cost matters and you want the cheaper blended price.

Choose o4 Vision if

  • You want the higher average benchmark score in this index.
  • You need the larger 200,000-token context window.

FAQ

Is Gemini 2.5 Pro Reasoning better than o4 Vision?

On the index average, o4 Vision leads Gemini 2.5 Pro Reasoning by 0.7 points (84.5 versus 83.8). The better choice depends on price, context and your task. Gemini 2.5 Pro Reasoning wins 5 benchmarks, o4 Vision wins 7.

Which is cheaper, Gemini 2.5 Pro Reasoning or o4 Vision?

Gemini 2.5 Pro Reasoning is cheaper on a blended 3:1 basis at about $29.59 per million tokens, versus $35.27 for o4 Vision.

Which has the larger context window?

o4 Vision has the larger context window at 200,000 tokens. Gemini 2.5 Pro Reasoning has 128,000 tokens.

Are these models open weights?

Gemini 2.5 Pro Reasoning is proprietary; o4 Vision is proprietary.

Which should I choose for production?

If you need a single default, start with o4 Vision for quality-sensitive work and Gemini 2.5 Pro Reasoning for high-volume, well-scoped tasks. Run both on a sample of your own traffic before locking in a choice.

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