Overview
Gemini 3.5 Pro is the flagship "Pro" tier of Google DeepMind's Gemini 3.5 family. Google introduced the family at Google I/O on May 19, 2026 under the banner "frontier intelligence with action," but on that day only Gemini 3.5 Flash actually shipped. For Gemini 3.5 Pro, Google's official blog said only: "We're also hard at work on 3.5 Pro. It's already being used internally, and we look forward to rolling it out next month." No specifications, benchmarks, pricing, or model ID were published.
As of a re-check on September 13, 2026, Gemini 3.5 Pro still has not been generally released. It does not appear in the official Gemini API changelog, on Google's developer pricing page, or in the Gemini API model list, where the only Pro-tier entries remain gemini-3.1-pro-preview and gemini-2.5-pro. The model has been described as in internal use and limited enterprise preview; the "next month" rollout Google indicated at I/O has not happened.
Positioned above Gemini 3.5 Flash, Gemini 3.5 Pro is expected to be Google's top reasoning and multimodal model, succeeding Gemini 3.1 Pro and absorbing the heavy frontier workloads. Widely-circulated figures such as a 2-million-token context window, a "Deep Think" reasoning mode, and roughly $15/$60-per-million-token pricing come from third-party tech press and analyst speculation — Google has not confirmed any of them. Treat every number for Gemini 3.5 Pro as unconfirmed until Google publishes an official model card.
| Released | 2026-05-19 |
|---|---|
| License | Proprietary (Google / Google DeepMind). Closed model offered as a hosted API service; no model weights or license terms have been published. |
| Weights | API only |
| Architecture | Not disclosed. Google has published no architecture details for Gemini 3.5 Pro. Like the rest of the Gemini line it is a natively multimodal transformer-based model, but parameter counts, mixture-of-experts structure, and training details are unpublished. |
| Modalities | text, images, audio, video, code |
| Status | Announced but not released. Unveiled at Google I/O on 2026-05-19 as "coming next month"; in internal/limited preview only. Re-checked on 2026-09-13: still absent from the public Gemini API model list, where the only Pro-tier entries are gemini-3.1-pro-preview and gemini-2.5-pro. |
Strengths
- Top tier of the Gemini 3.5 family, positioned as Google's most capable model above the already-strong Gemini 3.5 Flash
- Natively multimodal lineage (text, images, audio, and video) carried over from the rest of the Gemini line
- Designed for frontier reasoning, agentic action, and very long context — the workloads Google previously routed to its largest Gemini Pro/Ultra tiers
- Backed by Google's Gemini API, Vertex AI, and Gemini Enterprise distribution once it ships
Best for
- Frontier reasoning and complex problem-solving (intended successor to Gemini 3.1 Pro for the hardest tasks)
- Long-context document, codebase, and multimedia analysis
- Agentic and tool-using workflows that build on the Gemini 3.5 family's "intelligence with action" focus
- Advanced coding assistance and software-engineering automation
- Note: none of these are yet available in production — Gemini 3.5 Pro has not been released
Gemini Pro — every version
The full lineage of the Gemini Pro line, newest first. Every version has its own page — click any to compare specs, benchmarks and pricing.
| Version | Released | Context | License |
|---|---|---|---|
| Gemini 3.5 Pro | 2026-05-19 | — | Proprietary |
| Gemini 3.1 Procurrent | 2026-02-19 | 1M | Proprietary |
| Gemini 3 Pro | 2025-11-18 | — | Proprietary |
| Gemini 2.5 Pro | 2025-03-25 | — | Proprietary |
| Gemini 2.0 Pro | 2025-02-05 | — | Proprietary |
| Gemini 1.5 Pro | 2024-02-15 | — | Proprietary |
| Gemini 1.0 Ultra | 2024-02-08 | — | Proprietary |
| Gemini 1.0 Pro | 2023-12-13 | — | Proprietary |
FAQ
Has Gemini 3.5 Pro been released?
No. Gemini 3.5 Pro was announced at Google I/O on May 19, 2026, but only Gemini 3.5 Flash shipped that day. Google said Pro was "already being used internally" and would roll out "next month." As of a re-check on September 13, 2026 it still has not been generally released and is not listed in the public Gemini API model list, changelog, or pricing page.
What is the difference between Gemini 3.5 Pro and Gemini 3.5 Flash?
Flash is the faster, cheaper, already-available tier of the Gemini 3.5 family (released May 19, 2026 at $1.50/$9 per million input/output tokens). Pro is meant to be the more capable flagship tier above Flash, aimed at the hardest reasoning, agentic, and long-context tasks — but it has not shipped, so its exact capabilities and price are not yet official.
What are Gemini 3.5 Pro's specs and pricing?
Google has not published official specs, benchmarks, a knowledge cutoff, or pricing for Gemini 3.5 Pro. Figures circulating online — such as a 2-million-token context window, a "Deep Think" mode, and roughly $15/$60 per million tokens — are third-party estimates, not confirmed by Google. For comparison, the shipped Gemini 3.5 Flash costs $1.50/$9 per million tokens and Gemini 3.1 Pro Preview costs $2/$12.
When will Gemini 3.5 Pro be available?
Google targeted "next month" from its May 19, 2026 announcement, pointing to a June 2026 launch, but it gave no specific date. The model has been in internal and limited enterprise preview. Until Google publishes an official model card and adds it to the Gemini API, the release date and details remain unconfirmed.