GPT-5.5 vs Gemini 3.1 Pro Preview

GPT-5.5 from OpenAI and Gemini 3.1 Pro Preview from Google are shown side by side so you can compare pricing, model IDs, context and output limits, modalities, tool use, release details, and benchmark results where data is available.

Overall Recommendation

Gemini 3.1 Pro Preview is the stronger value and multimodal default: it is cheaper, supports video and audio, and leads GPT-5.5 on GPQA, HLE, SciCode, IFBench, and Tau2. Choose GPT-5.5 for its slightly higher overall Intelligence and Coding indexes and stable OpenAI workflows.

Recommendation based on GPT-5.5 (xhigh) vs Gemini 3.1 Pro Preview.

Comparison Highlights

GPT-5.5OpenAI
Gemini 3.1 Pro PreviewGoogle
Best For
Professional codingresearchdocument-heavy work
Multimodal reasoninggroundingmulti-step tool use
How To Read ItUse-case synthesis from model capabilities and positioning.
Workload Fit
CodingAnalysisKnowledge work
MultimodalAgentsGrounding
How To Read ItThe workloads each model is most directly shaped for.
Input
$5/M
$2/MEdge
How To Read ItLower is better when prompts or retrieval payloads are large.
Output
$30/M
$12/MEdge
How To Read ItLower is better for reasoning-heavy or long-generation traffic.
Context length
1.1M
1M
How To Read ItHigher is better for repositories, retrieval packs, and transcripts.
Input modalities
Image, PDF, Text
Audio, Image, PDF, Text, VideoEdge
How To Read ItBroader input support reduces the need for separate vision or video models.

Model Selection Guide

GPT-5.5OpenAI

Choose GPT-5.5 When

  • A 54.8 Intelligence Index and 59.1 Coding Index in TokenHub’s xhigh profile
  • $5 input and $30 output per million tokens, with $0.50 cached input
  • A 1.05M context window, 128K maximum output, and text, image, and PDF input
Gemini 3.1 Pro PreviewGoogle

Choose Gemini 3.1 Pro Preview When

  • A 55.5 Coding Index plus 94.1 GPQA and 44.7 HLE scores in TokenHub
  • $2 input and $12 output per million tokens, with a 1.048M context window
  • The broadest input coverage here: text, image, video, audio, and PDF

Basic Information

GPT-5.5OpenAI
Gemini 3.1 Pro PreviewGoogle

Name

GPT-5.5GPT-5.5

Model id

GPT-5.5gpt-5.5

Intro

GPT-5.5GPT-5.5 is described by OpenAI as a smarter frontier model for coding, research, data analysis, and professional knowledge work. The official launch messaging emphasizes higher capability, better speed than previous difficult-work models, and strong performance on tasks involving documents and structured analysis. Its description should focus on broad professional intelligence rather than a single niche.

Author

GPT-5.5OpenAI

Released date

GPT-5.52026-04-23

Context length

GPT-5.51.1M

Max output tokens

GPT-5.5128K

Name

Gemini 3.1 Pro PreviewGemini 3.1 Pro Preview

Model id

Gemini 3.1 Pro Previewgemini-3.1-pro-preview

Intro

Gemini 3.1 Pro PreviewGemini 3.1 Pro Preview is presented as a reliability-focused refinement of Gemini 3 Pro. Google’s preview notes emphasize better thinking, token efficiency, grounding, factuality, software engineering, agentic tool use, and multi-step execution. The preview label matters: it should be described as an advanced but evolving model for teams testing the next Pro behavior.

Author

Gemini 3.1 Pro PreviewGoogle

Released date

Gemini 3.1 Pro Preview2026-02-19

Context length

Gemini 3.1 Pro Preview1M

Max output tokens

Gemini 3.1 Pro Preview65.5K

Pricing

GPT-5.5OpenAI
Gemini 3.1 Pro PreviewGoogle

Input

GPT-5.5$5/M

Output

GPT-5.5$30/M

Cached input

GPT-5.5$0.5/M

Input

Gemini 3.1 Pro Preview$2/M

Output

Gemini 3.1 Pro Preview$12/M

Cached input

Gemini 3.1 Pro Preview$0.2/M

Capabilities

GPT-5.5OpenAI
Gemini 3.1 Pro PreviewGoogle

Reasoning

GPT-5.5

Knowledge

GPT-5.52025-12-01

Attachment

GPT-5.5

Input modalities

GPT-5.5Image, PDF, Text

Output modalities

GPT-5.5Text

Temperature

GPT-5.5

Tool use

GPT-5.5

Reasoning

Gemini 3.1 Pro Preview

Knowledge

Gemini 3.1 Pro Preview2025-01-01

Attachment

Gemini 3.1 Pro Preview

Input modalities

Gemini 3.1 Pro PreviewAudio, Image, PDF, Text, Video

Output modalities

Gemini 3.1 Pro PreviewText

Temperature

Gemini 3.1 Pro Preview

Tool use

Gemini 3.1 Pro Preview

Benchmark

GPT-5.5OpenAI
Gemini 3.1 Pro PreviewGoogle

Intelligence

wins54.8

Coding

wins59.1

Intelligence

46.5

Coding

55.5

Knowledge & Reasoning

GPQA

93.5%

HLE

44.3%

GPQA

wins94.1%

HLE

wins44.7%

Coding

SciCode

56.1%

Terminal-Bench Hard

wins60.6%

SciCode

wins58.9%

Terminal-Bench Hard

53.8%

Instruction Following & Agent Tasks

IFBench

75.9%

AA-LCR

wins74.3%

Tau2

93.9%

IFBench

wins77.1%

AA-LCR

72.7%

Tau2

wins95.6%

FAQ

Which model is better, GPT-5.5 or Gemini 3.1 Pro Preview?

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GPT-5.5 and Gemini 3.1 Pro Preview should be compared by workload. This page places price, context, output limits, capabilities, and benchmark data side by side. It is also relevant to: gemini vs chatgpt, chatgpt vs gemini.

Is Gemini 3.1 Pro Preview cheaper than GPT-5.5?

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Use the pricing rows above to compare input, output, and cached input prices for GPT-5.5 and Gemini 3.1 Pro Preview.

Which model supports a longer context length?

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GPT-5.5 lists 1.1M context length, while Gemini 3.1 Pro Preview lists 1M.

Can I access both models through TokenHub?

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If both models are available in the TokenHub catalog, you can route requests to GPT-5.5 and Gemini 3.1 Pro Preview through the TokenHub API.