Gemini 3.1 Pro
Google’s Pro-class Gemini for native multimodal and long-context work (current pin: gemini-3.1-pro-preview). Gemini 4 Argon is a separate public id.
Google’s Pro-class Gemini for hard reasoning and native multimodal work. Prefer API id gemini-3.1-pro-preview; Gemini 3.5 Pro remains partner-testing. This slug is not Gemini 4 Argon (gemini-4-argon, public 2026-10-13). On the Gemini API, gemini-2.5-pro has no announced shutdown date and is not deprecated; access is limited to projects that have already used it.
Why Gemini 3.1 Pro matters
Gemini 3.1 Pro remains the scored Pro-class escalate when natively multimodal inputs and very long context matter and Argon is not the pin you want. Flash (3.8) handles volume agents. Gemini 4 Argon (gemini-4-argon, 2026-10-13) is the newer public flagship and is not this slug. On the Gemini API, gemini-2.5-pro has no announced shutdown date; access is limited to projects that have already used it. Gemini 3.8 Live (2026-09-15) is a separate Live API voice SKU; Live Avatar (2026-09-24) adds video in Gemini Enterprise. Gemini 3.8 Flash TTS (2026-09-23) is speech generation, not Pro chat. Gemini 3.5 Pro is still rolling out — verify project access.
Vision · Audio input · Tool calling · Thinking · Coding
Last reviewed: 14 October 2026
When to choose Gemini 3.1 Pro
Decision guidance for architects—not a feature list.
Best for
- Native multimodal workloads
- Very long context analysis
- Google Cloud / Vertex stacks
- Research and synthesis over mixed media
Avoid if
- You are standardized only on OpenAI or Anthropic SDKs
- Open weights or fully air-gapped serving are required
Strengths
DataAIHub qualitative scores from 1 to 5, for architects. Not official benchmark results or a public ranking.
- Multimodal nativeness★★★★★
- Long context★★★★★
- Google Cloud fit★★★★★
- Open ecosystem lock-in risk★★☆☆☆
- Open weights★☆☆☆☆
Ecosystem
Built by
- Google
Gemini Pro is Google’s flagship multimodal foundation model class.
Competes with
- GPT-5
Competes on frontier multimodal capability and developer APIs.
- Claude Opus
Rival for long-context analysis and enterprise assistant workloads.
Works with
- LangChain
Common orchestration layer in front of Gemini APIs.
Recommended for
- Large language models
Reference multimodal proprietary model in Google’s ecosystem.
- Context Windows
Often cited for very long context multimodal workloads.
Often paired with
- Gemini 4 Argon
Argon (gemini-4-argon, 2026-10-13) is the newer public flagship. This slug stays Gemini 3.1 Pro.
How Gemini 3.1 Pro evolved
Key moments in chronological order.
- Product
gemini-2.5-pro has no Gemini API shutdown date
As of 2026-10-14, Google’s Gemini API deprecations page lists gemini-2.5-pro (released 2025-06-17) with no shutdown date. It is not deprecated. Access is limited to projects that have already used it, and the endpoint stays up until further notice. New projects should use gemini-3.5-flash-lite or gemini-3.8-flash.
- Model
Google opens Gemini 4 Argon on API id gemini-4-argon. It is a separate model from this Gemini 3.1 Pro slug. Standard price is $2/$10 per 1M tokens through 2026-11-30, then $4/$20 from 2026-12-01. gemini-3.8-flash remains the lower-priced workhorse.
- Product
Live Avatar adds lip-synced video to Gemini 3.8 Live in Gemini Enterprise. Custom avatars are allowlisted. It is a feature of the Live dialogue models, not a new Flash or Pro chat SKU. The announcement did not publish a separate API id or price.
- Model
Gemini 3.8 Flash TTS and Flash-Lite TTS are speech-generation models on the Gemini API and Google AI Studio. Flash TTS is for voice design; Flash-Lite TTS is the high-volume tier, with enterprise API described as coming soon. Not a replacement for gemini-3.8-flash. Confirm live model IDs in Google docs before pinning.
- Model
Live API speech-to-speech SKUs gemini-3.8-live and gemini-3.8-live-extended-thinking for real-time voice agents. Not a Flash/Pro chat replacement; pin Live IDs separately.
- Model
Current Flash workhorse (gemini-3.8-flash) for long-horizon coding and agents; same intro $0.75/$3.75 per 1M tokens through 2026-12-31. 3.8 Flash Cyber is Fairwind-only.
- Model
Gemini 3.5 Transcribe public preview
Dedicated speech-to-text models (gemini-3.5-transcribe and gemini-3.5-transcribe-live) succeed Chirp for recorded and streaming transcription in Gemini API preview.
- Model
Prior Flash workhorse (gemini-3.7-flash) for coding and agents; intro $0.75/$3.75 per 1M tokens through 2026-12-31. Succeeded as the default workhorse by 3.8 Flash; 3.7 remains supported.
- Model
Flash workhorse for agentic/coding/volume; Google confirms 3.5 Pro still testing with partners.
- Model
Current Pro-class pin (gemini-3.1-pro-preview) for hard multimodal reasoning while 3.5 Pro remains in partner testing.
- Model
Gemini 2.5 Pro class (legacy)
Earlier Pro-class Gemini for advanced reasoning and native multimodal workloads.
- Product
Long-context Gemini push
Million-token-class context becomes a Gemini product differentiator.
- Model
Gemini 1.5 era
Native multimodal + long context establishes Gemini’s modern identity.
- Model
Gemini family launches
Google’s unified multimodal foundation-model brand debuts.
- Leadership
Google Brain × DeepMind
Research and model product organizations consolidate under one AI org.
Overview
Capabilities
- Vision: Yes
- Audio input: Yes
- Tool calling: Yes
- Thinking: Yes
- MCP: No
- Coding: Yes
- Structured output: Yes
Technical specifications
- Provider
- License
- Proprietary
- Context window
- 1.0M
- Parameters
- Undisclosed
- Release
- 2026-02
- Modalities
- Text, Image, Audio, Video
- Vision
- Yes
- Audio input
- Yes
- Tool calling
- Yes
- Thinking
- Yes
- MCP
- No
- Open weights
- No
- API
- Yes
- Pricing (input)
- ~$2 / 1M tokens (<200K); ~$4 at ≥200K (3.1 Pro preview)
- Pricing (output)
- ~$12 / 1M tokens (<200K); ~$18 at ≥200K
Supported modalities
Text · Image · Audio · Video
Context window
1.0M (1,048,576 tokens)
Pricing
Verify Google AI / Vertex pricing; Flash tiers are cheaper for volume.
Availability
Pin gemini-3.1-pro-preview (and -customtools when needed). Gemini 3.5 Pro not broadly GA as of 2026-08. Gemini API deprecations list gemini-2.5-pro with no shutdown date; it is not deprecated, and access is limited to projects that have already used it. New projects should use gemini-3.8-flash or gemini-3.5-flash-lite. Gemini 4 Argon is the separate public id gemini-4-argon (2026-10-13). Gemini 3.5 Transcribe (gemini-3.5-transcribe / -live) is a separate speech-to-text preview as of 2026-08-26. Gemini 3.8 Live (gemini-3.8-live / gemini-3.8-live-extended-thinking, 2026-09-15) is a Live API voice SKU, not a Pro/Flash chat default. Live Avatar (2026-09-24) adds lip-synced video to 3.8 Live in Gemini Enterprise. Gemini 3.8 Flash TTS and Flash-Lite TTS (2026-09-23) are speech-generation siblings, not Pro chat — confirm model IDs in Google docs before pinning.
Use cases
- Long-context document and video understanding
- Multimodal research assistants
- Enterprise apps on Vertex AI
- Hard reasoning escalate above Flash
Strengths
- Very large context windows
- Strong native multimodality
- Deep Google Cloud / Vertex integration
Limitations
- Closed weights
- 3.1 Pro remains a preview ID; 3.5 Pro GA delayed
- Feature parity can differ across AI Studio vs Vertex
Related guides
Related benchmarks
Related research
- Gemini technical reports
Original Paper
- Introducing Gemini 4 Argon
Original Paper
Related GitHub
Related tools
Related rankings
Related comparisons
Companies
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