Gemini 3.1 Pro

Preview

This product or feature is a Generative AI Preview offering, subject to the "Pre-GA Offerings Terms" of the Google Cloud Service Specific Terms. For this Generative AI Preview offering, Customers may elect to use it for production or commercial purposes, or disclose Generated Output to third-parties, and may process personal data as outlined in the Cloud Data Processing Addendum, subject to the obligations and restrictions described in the agreement under which you access Google Cloud.

Gemini 3.1 Pro is our most advanced reasoning Gemini model, capable of solving complex problems. Gemini 3.1 Pro can comprehend vast datasets and challenging problems from different information sources, including text, audio, images, video, PDFs, and even entire code repositories with its 1M token context window.

For more information on using the latest Gemini models, see Get started with Gemini 3.

Quality improvements

Gemini 3.1 Pro includes several quality improvements:

• Improved SWE and agentic capabilities: Improved software engineering behavior and usability, with agentic improvements in domains like finance and spreadsheet applications.
• Improved token efficiency and thinking: More efficient thinking across various use cases.
• Expanded thinking levels: Introduces MEDIUM as a thinking_level parameter for more options to optimize trade-offs between cost, performance, and speed.

Custom tools endpoint

For those building with a mix of bash and custom tools, Gemini 3.1 Pro supports an additional endpoint: gemini-3.1-pro-preview-customtools. This endpoint is better at prioritizing custom tools (such as view_file or search_code). As gemini-3.1-pro-preview-customtools is optimized for agentic workflows that use custom tools and bash, you may see quality fluctuations in some use cases which don't benefit from such tools.

Pricing for gemini-3.1-pro-preview-customtools is identical to Gemini 3.1 Pro. Provisioned Throughput (PT) isn't supported on gemini-3.1-pro-preview-customtools, and multimodal requests on gemini-3.1-pro-preview-customtools enforce legacy input limits (up to 30 MiB per image and 10 HTTP or HTTPS image URLs, 50 MiB and 1,000 pages per PDF, 7 MiB per plain-text file, and 1 HTTP or HTTPS audio or video URL per request).

Try in Agent Studio View in Model Garden Deploy example app Pricing

Note: "Deploy example app" requires a Google Cloud project with billing and Agent Platform API enabled.

Model ID	gemini-3.1-pro-preview
Modalities	description Text Input and output photo Image Input only mic Audio Input only videocam Video Input only
Token limits	Context window	1,048,576
	Maximum output tokens	65,536
Capabilities	Thinking Supported System instructions Supported Structured output Supported Context caching Implicit context caching, explicit context caching Supported RAG Engine Supported Tuning Not supported Agentic video understanding Not supported
Tools	Grounding Google Search, Parallel Web Search, Exa Web Search Supported Code execution Supported Function calling Supported URL context Supported Computer use Not supported
APIs	GenerateContent API Supported Interactions API Supported Gemini Live API Not supported Count Tokens API Supported Chat Completions API Supported
Consumption options	Provisioned Throughput Supported Batch inference Supported Pay-as-you-go Standard PayGo, Flex PayGo, Priority PayGo Supported Fixed quota Not supported
Input size limit	GenerateContent API: 500 MiB compressed Interactions API: 256 MiB compressed (synchronous or streaming); 9.75 MiB uncompressed (deferred, when background and store are true)
Interactions API URI limit	Up to 100 distinct Cloud Storage (gs://) URIs per request across all modalities on the Interactions API, including URIs carried forward from earlier turns using previous_interaction_id. generateContent supports gs:// URIs up to the per-modality model item limits (up to 6,500 combined multimodal files when including plain-text files).
Technical specifications	Image	Maximum images per prompt: 3,000 (images and PDFs combined) Maximum inline part size (GenerateContent API): 256 MB Maximum file size per file from Cloud Storage: 2 GiB minus 500 KiB Maximum file size per file from public HTTP or HTTPS URLs: 15 MiB Maximum file size per file for direct local uploads in the console: 7 MiB inline (up to 50 MiB staged to Cloud Storage) Maximum file size per file for Google Drive imports in the console: 7 MB (10 MB total) Default resolution tokens: 1,120 Supported MIME types: image/png, image/jpeg, image/webp, image/heic, image/heif
	Text	Maximum number of files per prompt: 3,000 PDFs (shared with images; up to 6,500 total files when including plain text) Maximum number of pages per file: 3,000 Maximum inline part size (GenerateContent API): 256 MB Maximum file size per file from Cloud Storage: 2 GiB minus 500 KiB Maximum file size per file from public HTTP or HTTPS URLs: 15 MiB Maximum file size per file for direct local uploads in the console: 7 MiB inline (up to 50 MiB staged to Cloud Storage) Maximum file size per file for Google Drive imports in the console: 7 MB (10 MB total) Default resolution tokens: 560 OCR for scanned PDFs: Not used by default Supported MIME types: application/pdf, text/plain
	Video	Maximum video length (with audio): Approximately 45 minutes Maximum video length (without audio): Approximately 1 hour Maximum number of videos per prompt: 10 Maximum inline part size (GenerateContent API): 256 MB Maximum file size per file from Cloud Storage: 2 GiB minus 500 KiB Maximum file size per file from public HTTP or HTTPS URLs: 15 MiB Default resolution tokens per frame: 70 Supported MIME types: video/x-flv, video/quicktime, video/mpeg, video/mpegs, video/mpg, video/mp4, video/webm, video/wmv, video/3gpp
	Audio	Maximum audio length per prompt: Approximately 8.4 hours, or up to 1 million tokens Maximum number of audio files per prompt: 1,000 Maximum inline part size (GenerateContent API): 256 MB Maximum file size per file from Cloud Storage: 2 GiB minus 500 KiB Maximum file size per file from public HTTP or HTTPS URLs: 15 MiB Speech understanding for: Audio summarization, transcription, and translation Supported MIME types: audio/x-aac, audio/flac, audio/mp3, audio/m4a, audio/mpeg, audio/mpga, audio/mp4, audio/ogg, audio/pcm, audio/wav, audio/webm
	Parameter defaults	Temperature: 0.0-2.0 (default 1.0) topP: 0.0-1.0 (default 0.95) topK: 64 (fixed) candidateCount: 1–8 (default 1)
Supported regions	Model availability	Global: global
Versions	gemini-3.1-pro-preview Launch stage: Public preview Release date: February 19, 2026 gemini-3.1-pro-preview-customtools* Launch stage: Public preview Release date: February 23, 2026

^* Provisioned Throughput (PT) isn't supported for this endpoint, and legacy multimodal file size, page, and HTTP or HTTPS URL limits apply (see Custom tools endpoint).