Gemini 3.1 Pro vs GPT-5.1-Codex-Max: price, context and capabilities

Choose Gemini 3.1 Pro for very long inputs and the latest release; on the other points the two are level or the data is missing.

In short

  • A price comparison is not possible: one of them has no comparable published price.
  • Gemini 3.1 Pro reads more per request: 1.05M tokens against 400k.
  • Gemini 3.1 Pro is the newer model (February 2026, against Dec 4, 2025).
  • Only Gemini 3.1 Pro offers prompt caching.

Open in the full comparison table

Which should you choose?

Each answer below comes straight from the published prices, specifications and independent benchmark results.

Very long inputs

Choose Gemini 3.1 Pro

Gemini 3.1 Pro reads up to 1.05M tokens per request, against 400k for GPT-5.1-Codex-Max.

Latest release

Choose Gemini 3.1 Pro

Gemini 3.1 Pro is the newer release (February 2026, against Dec 4, 2025 for GPT-5.1-Codex-Max).

Specifications side by side

Gemini 3.1 ProGPT-5.1-Codex-Max
ProviderGoogleOpenAI
CategoryLanguage modelsLanguage models
StatusPreviewDeprecated
Headline price$4.50 / 1M tokensNo data
Input$2.00 / 1M tokensNo data
Output$12.00 / 1M tokensNo data
Cached input$0.20 / 1M tokensNo data
Context window1.05M400k
Max output66k128k
ReleasedFebruary 2026Dec 4, 2025
Knowledge cutoffNo dataSeptember 2024
LicenceProprietaryProprietary
CapabilitiesVision, Reasoning, Tool calling, Structured output, Prompt caching, Batch APIVision, Reasoning, Tool calling, Structured output, Batch API
API model idgemini-3.1-pro-previewgpt-5.1-codex-max

Benchmarks side by side

Leader in bold.

BenchmarkGemini 3.1 ProGPT-5.1-Codex-Max
Intelligence Index 29.7 No data
Terminal-Bench Hard 53.8% No data
SciCode 58.7% No data
GPQA Diamond 94.1% No data
Humanity's Last Exam 47% No data
IFBench (instruction following) 77.1% No data
τ²-Bench (agentic tool use) 95.6% No data
MMMU-Pro (visual reasoning) 82.4% No data
Long-context reasoning (AA-LCR) 82% No data

Independent evaluations by Artificial Analysis, run the same way for every model, at the reasoning setting shown. Percentages unless marked as an index.

Frequently asked questions

Should I choose Gemini 3.1 Pro or GPT-5.1-Codex-Max?

Choose Gemini 3.1 Pro for very long inputs and the latest release; on the other points the two are level or the data is missing.

Which is cheaper, Gemini 3.1 Pro or GPT-5.1-Codex-Max?

A price comparison is not possible: one of them has no comparable published price.

Which has the larger context window, Gemini 3.1 Pro or GPT-5.1-Codex-Max?

Gemini 3.1 Pro reads more per request: 1.05M tokens against 400k.

What is the difference between Gemini 3.1 Pro and GPT-5.1-Codex-Max?

Gemini 3.1 Pro is made by Google and GPT-5.1-Codex-Max by OpenAI. A price comparison is not possible: one of them has no comparable published price. Gemini 3.1 Pro reads more per request: 1.05M tokens against 400k. Gemini 3.1 Pro is the newer model (February 2026, against Dec 4, 2025). Only Gemini 3.1 Pro offers prompt caching.

Which is newer, Gemini 3.1 Pro or GPT-5.1-Codex-Max?

Gemini 3.1 Pro was released on February 2026 and GPT-5.1-Codex-Max on Dec 4, 2025.