Google Gemini is a family of multimodal large language models by Google DeepMind, capable of understanding and generating text, images, audio, video, and code. As of May 2026, Gemini 3.5 Flash (released at Google I/O 2026) leads the stable lineup as the strongest agentic and coding model β outperforming Gemini 3.1 Pro on key benchmarks at 4Γ the speed of other frontier models β while Gemini 3.1 Pro Preview (2M token context) remains the flagship for deep reasoning. The API is accessible via two paths: the Gemini Developer API (API keys, Google AI Studio) and Vertex AI (enterprise GCP deployment with IAM). The official Python SDK is google-genai (pip install google-genai), offering both the classic generate_content and the new Interactions API (client.interactions.create()) designed for agentic workflows.
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This topic spans 17 focused tables and 134 indexed concepts, 113 flashcards. Below is a complete table-by-table outline of this topic, spanning foundational concepts through advanced details.
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Table 1: Model Variants
Each Gemini generation brings a different trade-off of intelligence, speed, and cost; choosing the right model β and knowing which are stable versus preview versus shutting down β is the single most important configuration decision in any Gemini project.
| Model | Example | Description | |
|---|---|---|---|
model='gemini-3.5-flash' | β’ Current stable flagship β released May 19, 2026 (Google I/O 2026) β’ outperforms Gemini 3.1 Pro on coding and agentic benchmarks; 4Γ faster than other frontier models β’ 1M token context, 64K max output; thinking levels minimal/low/medium (default)/highβ’ free tier available; Computer Use not yet supported. | ||
model='gemini-3.1-pro-preview' | β’ Flagship for complex reasoning, multimodal, and vibe-coding tasks β’ 2M token context window β largest of any production model β’ thinking_level enum: LOW, MEDIUM, HIGH; no free tierβ’ separate gemini-3.1-pro-preview-customtools endpoint for prioritizing custom tools. | ||
model='gemini-3.1-flash-lite' | β’ Most cost-efficient stable model (GA May 7, 2026; replaces Preview) β’ optimized for high-volume agentic tasks, translation, simple data processing β’ free tier available; shutdown May 7, 2027. | ||
model='gemini-3-flash-preview' | β’ Earlier-generation preview β recommended migration to gemini-3.5-flashβ’ Agentic Vision: zooms, inspects, and manipulates images via code execution β’ thinking_level for latency control; free tier available; no shutdown date announced. | ||
model='gemini-2.5-flash' | β’ Widely-used stable model β best price-performance for low-latency, high-volume reasoning β’ 1M token context, 65K max output; thinking_budget or thinking_levelβ’ free tier available; shuts down October 16, 2026; migrate to gemini-3.5-flash. | ||
model='gemini-2.5-pro' | β’ Stable Pro for complex reasoning and coding tasks β’ 1M token context, 65K max output; adaptive thinking, implicit context caching β’ shuts down October 16, 2026; migrate to gemini-3.1-pro-preview. | ||
model='gemini-2.5-flash-lite' | β’ Budget stable model for high-throughput, latency-sensitive workloads β’ 1M token context; free tier available β’ shuts down October 16, 2026; migrate to gemini-3.1-flash-lite. | ||
AICore system service on Android Not accessible via Gemini API | β’ On-device edge AI for Android (developer preview) β’ two variants: Nano 4 Fast (E2B) and Nano 4 Full (E4B) β’ 140+ language support; 4Γ faster and 60% less battery than predecessor; runs offline. |