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Gemini 3.1 Flash TTS Preview vs GPT-5.5

Gemini 3.1 Flash TTS Preview (2026) and GPT-5.5 (2026) are frontier reasoning models from Google DeepMind and OpenAI. Gemini 3.1 Flash TTS Preview ships a 16K-token context window, while GPT-5.5 ships a 1.05M-token context window. This comparison covers specs, pricing, capabilities, benchmarks, provider availability, and production fit. It focuses on practical selection signals rather than broad model-family marketing. The goal is to make the tradeoff clear before deeper testing.

GPT-5.5 fits 66x more tokens; pick it for long-context work and Gemini 3.1 Flash TTS Preview for tighter calls.

Specs

Released2026-04-152026-04-23
Context window16K1.05M
Parameters
Architecturedecoder onlydecoder only
LicenseProprietaryProprietary
Knowledge cutoff-2025-12

Pricing and availability

Gemini 3.1 Flash TTS PreviewGPT-5.5
Input price-$5/1M tokens
Output price-$30/1M tokens
Providers-

Capabilities

Gemini 3.1 Flash TTS PreviewGPT-5.5
Vision
Multimodal
Reasoning
Function calling
Tool use
Structured outputs
Code execution

Benchmarks

No shared benchmark rows are currently sourced for this pair.

Deep dive

The capability footprint differs most on vision: GPT-5.5, multimodal input: GPT-5.5, reasoning mode: GPT-5.5, function calling: GPT-5.5, tool use: GPT-5.5, structured outputs: GPT-5.5, and code execution: GPT-5.5. Both models share the core language-model surface, so the practical split is not just feature count. Use those differences to decide whether the page is about raw model quality, agentic coding support, multimodal ingestion, or predictable structured API behavior.

Pricing coverage is uneven: Gemini 3.1 Flash TTS Preview has no token price sourced yet and GPT-5.5 has $5/1M input tokens. Provider availability is 0 tracked routes versus 1. Treat unknown pricing as an integration gap, then verify the route you will actually call before estimating production spend.

Choose Gemini 3.1 Flash TTS Preview when provider fit are central to the workload. Choose GPT-5.5 when coding workflow support, larger context windows, and broader provider choice are more important. For production, rerun your own prompts through the exact provider, region, and tool stack you plan to ship. This keeps the decision grounded in measurable tradeoffs instead of brand-level assumptions. It also helps separate model capability from provider packaging, which can change cost and latency.

FAQ

Which has a larger context window, Gemini 3.1 Flash TTS Preview or GPT-5.5?

GPT-5.5 supports 1.05M tokens, while Gemini 3.1 Flash TTS Preview supports 16K tokens. That gap matters most for long documents, large codebases, retrieval-heavy agents, and conversations where earlier context must remain visible.

Is Gemini 3.1 Flash TTS Preview or GPT-5.5 open source?

Gemini 3.1 Flash TTS Preview is listed under Proprietary. GPT-5.5 is listed under Proprietary. License labels affect whether you can self-host, redistribute weights, or rely only on hosted APIs, so confirm the upstream license before deployment.

Which is better for vision, Gemini 3.1 Flash TTS Preview or GPT-5.5?

GPT-5.5 has the clearer documented vision signal in this comparison. If vision is mission-critical, validate it against the provider endpoint because model-level support and API-level exposure can differ. Use this as a quick comparison signal, then confirm the provider-specific limits before committing to production.

Which is better for multimodal input, Gemini 3.1 Flash TTS Preview or GPT-5.5?

GPT-5.5 has the clearer documented multimodal input signal in this comparison. If multimodal input is mission-critical, validate it against the provider endpoint because model-level support and API-level exposure can differ.

Which is better for reasoning mode, Gemini 3.1 Flash TTS Preview or GPT-5.5?

GPT-5.5 has the clearer documented reasoning mode signal in this comparison. If reasoning mode is mission-critical, validate it against the provider endpoint because model-level support and API-level exposure can differ.

Where can I run Gemini 3.1 Flash TTS Preview and GPT-5.5?

Gemini 3.1 Flash TTS Preview is available on the tracked providers still being sourced. GPT-5.5 is available on OpenAI API. Provider coverage can affect latency, region availability, compliance posture, and fallback options.

Continue comparing

Last reviewed: 2026-04-29. Data sourced from public model cards and provider documentation.